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pneumonia.5,6 Similarly, in this series we established that necrotizing pneumonia was the commonest etiology of nontuberculous cavitary lesions. Other reports of cavitary lesions in children are usually only in the form of case reports with various causes including infectious, bronchiectasis, malignancy, immunodeficiency, rheumatologic diseases or congenital lung abnormalities.8–10 REFERENCES 1. Gadkowski LB, Stout JE. Cavitary pulmonary disease. Clin Microbiol Rev. 2008;21:305–333. 2. Cosgrove GP, Frankel SK, Brown KK. Challenges in pulmonary fibrosis. 3: Cystic lung disease. Thorax. 2007;62:820–829. 3. Vourtsi A, Gouliamos A, Moulopoulos L, et al. CT appearance of solitary and multiple cystic and cavitary lung lesions. Eur Radiol. 2001;11:612–622. 4. Al-Tawfiq JA, Saadeh BM. Radiographic manifestations of culture-positive pulmonary tuberculosis: cavitary or non-cavitary? Int J Tuberc Lung Dis. 2009;13:367–370. 5. Hacimustafaoglu M, Celebi S, Sarimehmet H, et al. Necrotizing pneumonia in children. Acta Paediatr. 2004;93:1172–1177. 6. Sawicki GS, Lu FL, Valim C, et al. Necrotising pneumonia is an increasingly detected complication of pneumonia in children. Eur Respir J. 2008;31:1285–1291. 7. Ramphul N, Eastham KM, Freeman R, et al. Cavitatory lung disease complicating empyema in children. Pediatr Pulmonol. 2006;41:750–753. 8. Levine D, Akikusa J, Manson D, et al. Chest CT findings in pediatric Wegener’s granulomatosis. Pediatr Radiol. 2007;37:57–62. 9. Chan PC, Huang LM, Wu PS, et al. Clinical management and outcome of childhood lung abscess: a 16-year experience. J Microbiol Immunol Infect. 2005;38:183–188. 10. Stanton M, Njere I, Ade-Ajayi N, et al. Systematic review and meta-analysis of the postnatal management of congenital cystic lung lesions. J Pediatr Surg. 2009;44:1027–1033.
PREVALENCE OF CONGENITAL CYTOMEGALOVIRUS INFECTION IN NIGERIA A PILOT STUDY
Bolajoko O. Olusanya, FRCPCH, PhD,* Tina M. Slusher, MD,† and Suresh B. Boppana, MD‡§ Abstract: Dried saliva specimens from 263 neonates in Lagos, Nigeria, were tested for cytomegalovirus (CMV) using real-time polymerase chain reaction. The results for 10 infants (3.8%, 95% confidence interval, 2.1–6.8) were found to be positive. Congenital CMV infection was not associated with any of the demographic or maternal factors including HIV. These data demonstrate the high prevalence of congenital CMV infection and the feasibility of CMV screening by real-time polymerase chain reaction testing. Key Words: congenital CMV, saliva PCR, newborn screening, developing country Accepted for publication August 28, 2014. From the *Centre for Healthy Start Initiative, Lagos, Nigeria; †Department of Pediatrics, Hennepin County Medical Center, University of Minnesota, Minneapolis, Minnesota; ‡Department of Pediatrics; and §Department of Microbiology, University of Alabama at Birmingham, Alabama. This study was supported by the National Institute on Deafness and Other Communication Disorders (N01 DC50008). The authors have no conflicts of interest to disclose. Address for correspondence: Suresh B. Boppana, MD, Departments of Pediatrics and Microbiology, University of Alabama at Birmingham, CHB 114, 1600, 7th Ave South, Birmingham, AL 35233. E-mail: [email protected]. Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s Web site (www.pidj.com). Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved. DOI: 10.1097/INF.0000000000000555
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C
ytomegalovirus (CMV) is a frequent cause of congenital infection and a leading nongenetic cause of permanent congenital or early-onset hearing loss (PCEHL) in children.1,2 Although limited data suggest high prevalence of congenital CMV (cCMV) infection in developing countries with high maternal CMV seroprevalence, the burden of disease and natural history of cCMV infection, especially in sub-Saharan Africa, have not been well defined.1,3–5 Additionally, the role of cCMV in PCEHL in the African continent has not been examined, although infants with microcephaly have been reported to be significantly at risk for PCEHL in Nigeria.6 Early identification of infants with cCMV allows for prompt detection of children at risk for PCEHL who require appropriate intervention during critical stages of language development.1,2 Real-time polymerase chain reaction (PCR) testing of newborn saliva has been shown to be highly specific and sensitive for detecting CMVinfected infants.7,8 We therefore conducted a pilot study to determine the prevalence of cCMV in an inner-city community in Lagos, Nigeria, with a previously reported high occurrence of PCEHL.9
METHODS Infants were enrolled in the study by convenient sampling of neonates on admission between November 2012 and April 2013 at Island Maternity Hospital (IMH) and Massey Children’s Hospital (MCH) in Lagos, Nigeria, whose mothers gave consent to participate in the study. Demographic data and medical history were obtained from hospital records and ethical approval from the Lagos State Government Health Service Commission. Dried saliva swabs were collected, labeled with a unique ID number and transported to the University of Alabama at Birmingham for testing by real-time PCR for CMV without the DNA extraction step as described.7,8 A sample was considered positive if one or more international units (IU) per reaction was detected. The detection limit of this PCR assay was determined to be 116 IU/mL of the sample (1.72 ge/ mL = 1 IU/mL) using the Acrometrix (Life Technologies, Grand Island, NY) CMV international standards. No follow-up visits were included, but parents were informed of the infant’s CMV status for further medical attention. HIV 1 and HIV 2 testing was routinely conducted during pregnancy using 2 rapid immunochromatographic screening test kits.9 Two negative or positive results are confirmatory for HIV status. Discordant results were resolved with enzyme-linked immunosorbent assay. Data were analyzed using SPSS statistical package version 21 (IBM Corp, Armonk, NY). To determine differences between infants with and without cCMV, we used a case-control sample in which infants with CMV were matched on the basis of gender to infants without CMV in the ratio of 1:10. Gender was selected as the matching criterion because of the potential confounding effect of the high frequency of glucose6-phosphate dehydrogenase deficiency in male infants in the study population. The controls were selected from infants with the closest dates of birth from the same hospital. Maternal age, ethnicity, gravidity, parity, mode of delivery, HIV status, multiple gestation, gestational age, birth weight, presence of neonatal jaundice and admission status were compared between CMV-infected and CMVuninfected infants. Statistical significance was determined by Pearson χ2 test or Fisher exact for categorical variables and student t test for continuous variables.
RESULTS Of the 263 infants tested, 10 (6 females and 4 males) were CMV positive, amounting to a prevalence rate of 3.8% (95% confidence interval: 2.1–6.9%). The prevalence of cCMV was not significantly different between the 2 hospitals: 3.4% (5 of 149) versus 4.4% (5 of 114). The characteristics of CMV-infected newborns are shown in Table 1. Mean age of mothers with CMV-infected babies © 2015 Wolters Kluwer Health
The Pediatric Infectious Disease Journal • Volume 34, Number 3, March 2015
Congenital CMV in Nigeria
TABLE 1. Characteristics of Infants with Congenital CMV Infection Status at Screening
Mother’s Age (years)
Mode of Delivery
Gestation
Gestational Age (weeks)
Birth Weight (kg)
1
Out-born
30
SVD
Singleton
39
Missing
2 3 4 5 6 7 8
Out-born Inborn Inborn Out-born Out-born Inborn Out-born
30 38 38 30 22 31 34
SVD SVD BREECH EMCS SVD EMCS EMCS
Singleton First twin Second twin One of triplet Singleton Singleton Singleton
39 31 31 38 39 37 30
Missing 1.0 1.0 Missing N 3.30 1.25
9 10
Inborn Inborn
21 23
EMCS EMCS
Singleton Singleton
39 37
3.75 2.90
Clinical Features Symptomatic: hepatosplenomegaly and bronchopneumonia Asymptomatic Asymptomatic, NNJ Asymptomatic, NNJ Asymptomatic Asymptomatic Asymptomatic, NNJ Symptomatic: hepatosplenomegaly and bronchopneumonia, and NNJ Asymptomatic Asymptomatic
SVD indicates spontaneous vertex delivery; EMCS, emergency caesarean delivery; NNJ, treated for jaundice.
was 29.7 ± 6.1 years (IMH: 30.2 ± 8.04; MCH: 29.2 ± 4.38 years). Mean gestational age for CMV-infected infants was 35.9 ± 4.0 weeks (IMH: 35.0 ± 3.74; MCH: 37.0 ± 3.94 weeks), with a mean birth weight of 2.2 ± 1.3 kg (IMH: 2.39 ± 1.30; MCH: 3.23 ± 1.06 kg). Of the infected children, 2 infants were symptomatic. Both infants had hepatosplenomegaly and bronchopneumonia, and 1 baby had neonatal jaundice also. Maternal HIV status was known for 162 infants including 8 congenitally infected children. The prevalence of maternal HIV infection was 4.9% (6 of 162), and none of the CMV-infected babies was born to a HIV-positive mother. There were no statistically significant differences between CMV-infected infants and their matched controls with respect to maternal age, ethnicity, gravidity, parity, gestational age, maternal HIV status and birth weight (see Table, Supplemental Digital Content 1, http:// links.lww.com/INF/C19).
DISCUSSION This study utilized a virologic assay that is reliable and convenient to identify CMV-infected newborns. By eliminating the requirement for DNA extraction, this PCR assay has significant cost savings also. The results from this population with near-universal seroimmunity demonstrated the high prevalence of cCMV and the feasibility of screening newborns by real-time PCR of dried-saliva swabs in resource-poor settings. The prevalence of cCMV in this study falls within the reported range of 0.9% (Mexico) and 5.4% (Gambia) for developing countries but well over 0.5–0.7% reported in developed countries.1,3–5 Our findings are consistent with those reported in a recent study from Zambia in which cCMV, based on the detection of CMV DNA in saliva, urine or sera or on the detection of serum CMV-IgM antibodies, was detected in 3.8% (15 of 395) of neonatal admissions in the first 3 weeks in a population with high maternal HIV prevalence.3 A study from the Gambia reported significantly higher prevalence of cCMV (5.4%, 40 of 741), which was associated with active placental malarial infection.4 Although CMV seroprevalence was not determined as part of this study, a previous study among pregnant women in Lagos, Nigeria, showed that 97.2% were CMVIgG positive.10 It is therefore likely that most women in our study were seroimmune before pregnancy. High prevalence (2.9%, 22 of 748) of cCMV in HIV-exposed infants was also documented in a recent study from South Africa.5 Compared with findings from Zambia and South Africa, none of the HIV-exposed infants was CMV-infected in our study.3,5 In the Zambian study, the prevalence of cCMV was 11.4% and 2.1% among neonates born to HIV-infected and HIV-uninfected mothers, respectively.3 In Western Cape, South Africa, 2.9% of infants born to 748 © 2015 Wolters Kluwer Health
HIV-infected mothers had cCMV.5 The prevalence of maternal HIV infection of 4.9% in our study population is consistent with previous data from this inner-city community.8 HIV-infection status was known for 162 mothers including 8 mothers with CMV-infected newborns, and none of the babies with cCMV was born to HIV-infected mothers. However, the number of women with HIV infection in this study is too small to determine the role of maternal HIV infection on intrauterine CMV transmission, and therefore, the association between cCMV and maternal HIV in this population merits further research. There were no associations between congenital CMV and maternal age, parity, mode of delivery, gestational age, birth weight, gender and jaundice. A major limitation of this study is the small sample size and the use of convenience sampling. Thus, it is not clear whether these data are representative of cCMV prevalence in the population in Nigeria. Additionally, infected children were not followed to document long-term outcomes. Although the real-time PCR assay has been shown to be highly specific in previous studies in the United States, it is possible that the rate of false-positive PCR results could be higher in populations with concurrent maternal infections.7,8 Nevertheless, the findings of this study underscore the need for a prospective newborn CMV screening study with longterm follow-up to document the natural history and disease burden of cCMV in this population. In addition, the utility of the real-time PCR assay should be evaluated in larger studies in such populations. It is crucial to examine the role of cCMV among infants with congenital, early-onset/late-onset, fluctuating and progressive sensorineural hearing loss to develop evidence-based guidelines for intervention advocacy for at-risk infants. Overall, this pilot study and the follow-up research should fill an important epidemiologic gap in the study of cCMV infection in sub-Saharan Africa.
ACKNOWLEDGMENTS We thank the management of IMH and Massey Street Children’s Hospital, Lagos, Nigeria, for their support in facilitating access to the participants in this study. REFERENCES 1. Manicklal S, Emery VC, Lazzarotto T, et al. The “silent” global burden of congenital cytomegalovirus. Clin Microbiol Rev. 2013;26:86–102. 2. Dahle AJ, Fowler KB, Wright JD, et al. Longitudinal investigation of hearing disorders in children with congenital cytomegalovirus infection. J Am Acad Audiol. 2000;11:283–290. 3. Mwaanza N, Chilukutu L, Tembo J, et al. High rates of congenital cytomegalovirus infection linked with maternal HIV infection among neonatal admissions at a large referral center in sub-Saharan Africa. Clin Infect Dis. 2014;58:728–735.
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4. van der Sande MA, Kaye S, Miles DJ, et al. Risk factors for and clinical outcome of congenital cytomegalovirus infection in a peri-urban West-African birth cohort. PLoS One. 2007;2:e492. 5. Manicklal S, van Niekerk AM, Kroon SM, et al. Birth prevalence of congenital cytomegalovirus among infants of HIV-infected women on prenatal antiretroviral prophylaxis in South Africa. Clin Infect Dis. 2014;58:1467–1472. 6. Olusanya BO. Risk of sensorineural hearing loss in infants with abnormal head size. Ann Afr Med. 2013;12:98–104. 7. Boppana SB, Ross SA, Shimamura M, et al; National Institute on Deafness and Other Communication Disorders CHIMES Study. Saliva polymerasechain-reaction assay for cytomegalovirus screening in newborns. N Engl J Med. 2011;364:2111–2118. 8. Ross SA, Ahmed A, Palmer AL, et al; for the National Institute on Deafness and Other Communication Disorders CHIMES Study. Detection of congenital cytomegalovirus infection by real-time polymerase chain reaction analysis of saliva or urine specimens. J Infect Dis 2014;210:1415–1418. 9. Olusanya BO, Afe AJ, Onyia NO. Infants with HIV-infected mothers in a universal newborn hearing screening programme in Lagos, Nigeria. Acta Paediatr. 2009;98:1288–1293. 10. Akinbami AA, Rabiu KA, Adewunmi AA, et al. Seroprevalence of cytomegalovirus antibodies amongst normal pregnant women in Nigeria. Int J Womens Health. 2011;3:423–428.
SUBACUTE OSTEOMYELITIS OF THE FEMUR DUE TO FUSOBACTERIUM NUCLEATUM IN A 7-YEAR-OLD BOY Emily Budd, BM,* David S. Johnson, MPhil,† Eva Thomas, PhD,‡ and Manish Sadarangani, DPhil*§ Abstract: Subacute hematogenous osteomyelitis is an insidious infection, which commonly has a delayed diagnosis. We describe the case of a 7-year-old boy with subacute osteomyelitis, which was initially considered to be a bone tumor. Infection should be considered in all cases of bone pain, especially in children, even in the absence of typical systemic features of inflammation. Key Words: anaerobic, bone, child, infection Accepted for publication August 28, 2014. From the *Department of Pediatrics, BC Children’s Hospital and University of British Columbia, Vancouver, BC, Canada; †Department of Orthopaedics, Stockport NHS Foundation Trust, Stepping Hill Hospital, Stockport, SK2 7JE, United Kingdom; ‡Division of Microbiology, Virology and Infection Control, Department of Pathology, Children’s and Women’s Health Centre of BC, Vancouver, BC, Canada; and §Department of Paediatrics, University of Oxford, Oxford, United Kingdom. The authors have no conflicts of interest or funding to disclose. Address for Correspondence: Dr Manish Sadarangani, Department of Paediatrics, University of Oxford, Level 2, Children’s Hospital, Oxford OX3 9DU, United Kingdom. E-mail: [email protected]. Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s website (www.pidj.com). Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved. DOI: 10.1097/INF.0000000000000558
CASE REPORT Subacute hematogenous osteomyelitis (AHO) is an insidious infection, which commonly has a delayed diagnosis. We describe the case of a 7-year-old boy with subacute osteomyelitis, which was initially considered to be a bone tumor. Infection should be considered in all cases of bone pain, especially in children, even in the absence of typical systemic features of inflammation. A previously healthy 7-year-old boy developed onset of pain in his left lower leg, predominantly in his knee. There was no definite history of trauma other than mild knocks while playing on a trampoline and wrestling with his brother approximately 1–2 days before onset of symptoms. During the next few weeks, he presented to 3 hospitals with episodes of increased pain. On each occasion it was felt he had a soft
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tissue injury and his symptoms subsequently eased but did not fully resolve. On the last occasion, when he had sustained a minor head injury requiring overnight admission, the knee pain was noted and radiographs taken were normal. He was afebrile with normal vital signs. No further investigations were ordered at that stage as he was otherwise well. Four weeks after the onset of his symptoms, he was referred to an orthopedic surgeon by his family doctor due to ongoing knee pain. He was well and afebrile, but had a limp holding the left knee flexed. He was tender throughout the lower limb but mostly over the lower thigh. There was no knee effusion and, when relaxed, there was full range of movement of the knee. There were no local signs of inflammation, with only a few nontender lymph nodes present in each groin. Radiographs of his hips and left knee and an ultrasound scan of the left hip were normal. A magnetic resonance scan showed a cystic lesion in the medial femoral condyle with associated bone bruising and a pathologic fracture, with involvement of the distal metaphysis. The lesion was suspected to be a chondroblastoma, although a clear cell chondrosarcoma was also considered. As the family moved to Canada from the UK a few days later, referral to the local oncology service at their destination was made. Shortly after the flight to Canada his pain greatly increased and he was admitted for further investigation of a presumptive bone malignancy. He had a temperature of 38.1°C and vital signs were otherwise normal. He had a knee effusion with marked tenderness and very limited range of motion in the hip, knee and ankle. Initial investigations revealed a normal white blood cell count (9.7 × 109/L) (neutrophils 5.6 × 109/L, lymphocytes 2.9 × 109/L) and platelet count (298 × 109/L), with a hemoglobin of 119 g/L and microcytosis (mean corpuscular volume 72.6 fL). The erythrocyte sedimentation rate was elevated (55 mm/h), as was the C-reactive protein (200 mg/L). The coagulation profile, lactate dehydrogenase, uric acid, renal and liver function tests were normal. One set of blood cultures was taken (one aerobic and one anaerobic bottle) and was subsequently negative. He was initially treated supportively with analgesia and anti-inflammatory drugs, but an increase in the swelling over the next 48 hours prompted an emergency arthotomy on the medial aspect of the knee. Purulent fluid was obtained under pressure from the distal femur, and therapy was commenced with cefazolin (100 mg/kg/d) postoperatively, as standard empiric therapy for osteoarticular infections. Four specimens were taken during surgery and transported to the laboratory in plain sterile containers, with all specimens being processed within 4 hours. White blood cells were seen on microscopy, with no organisms on Gram stain. Fusobacterium nucleatum was subsequently isolated from three specimens by culture and confirmed by 16S DNA sequencing, confirming the diagnosis of subacute osteomyelitis. He was treated with 2 weeks of intravenous clindamycin (40 mg/kg/d) and penicillin G (250,000 units/kg/d) followed by 4 weeks of oral clindamycin (30 mg/ kg/d), the organism being susceptible to these antibiotics. Dual therapy was used initially due to the longstanding nature of symptoms and to achieve good bactericidal effect, with ongoing therapy with clindamycin only due to its excellent bone penetration. Duration was guided by clinical response and review of the literature regarding pediatric Fusobacterium bone and joint infections. He made a full recovery with no residual pain, limb length discrepancy or growth plate disturbance at 2 years post-surgery.
DISCUSSION Osteomyelitis can be broadly categorized based on duration of symptoms into acute, subacute and chronic, although absolute cut-offs to separate these categories have not been defined. Chronic osteomyelitis is distinguished histologically by the presence of necrotic tissue and involucrum. Subacute osteomyelitis is a slowly progressive primary bone infection with symptoms taking over 2 weeks to develop.1 In contrast to AHO, there is usually no fever or leukocytosis in subacute © 2015 Wolters Kluwer Health
Olusanya et al
pneumonia.5,6 Similarly, in this series we established that necrotizing pneumonia was the commonest etiology of nontuberculous cavitary lesions. Other reports of cavitary lesions in children are usually only in the form of case reports with various causes including infectious, bronchiectasis, malignancy, immunodeficiency, rheumatologic diseases or congenital lung abnormalities.8–10 REFERENCES 1. Gadkowski LB, Stout JE. Cavitary pulmonary disease. Clin Microbiol Rev. 2008;21:305–333. 2. Cosgrove GP, Frankel SK, Brown KK. Challenges in pulmonary fibrosis. 3: Cystic lung disease. Thorax. 2007;62:820–829. 3. Vourtsi A, Gouliamos A, Moulopoulos L, et al. CT appearance of solitary and multiple cystic and cavitary lung lesions. Eur Radiol. 2001;11:612–622. 4. Al-Tawfiq JA, Saadeh BM. Radiographic manifestations of culture-positive pulmonary tuberculosis: cavitary or non-cavitary? Int J Tuberc Lung Dis. 2009;13:367–370. 5. Hacimustafaoglu M, Celebi S, Sarimehmet H, et al. Necrotizing pneumonia in children. Acta Paediatr. 2004;93:1172–1177. 6. Sawicki GS, Lu FL, Valim C, et al. Necrotising pneumonia is an increasingly detected complication of pneumonia in children. Eur Respir J. 2008;31:1285–1291. 7. Ramphul N, Eastham KM, Freeman R, et al. Cavitatory lung disease complicating empyema in children. Pediatr Pulmonol. 2006;41:750–753. 8. Levine D, Akikusa J, Manson D, et al. Chest CT findings in pediatric Wegener’s granulomatosis. Pediatr Radiol. 2007;37:57–62. 9. Chan PC, Huang LM, Wu PS, et al. Clinical management and outcome of childhood lung abscess: a 16-year experience. J Microbiol Immunol Infect. 2005;38:183–188. 10. Stanton M, Njere I, Ade-Ajayi N, et al. Systematic review and meta-analysis of the postnatal management of congenital cystic lung lesions. J Pediatr Surg. 2009;44:1027–1033.
PREVALENCE OF CONGENITAL CYTOMEGALOVIRUS INFECTION IN NIGERIA A PILOT STUDY
Bolajoko O. Olusanya, FRCPCH, PhD,* Tina M. Slusher, MD,† and Suresh B. Boppana, MD‡§ Abstract: Dried saliva specimens from 263 neonates in Lagos, Nigeria, were tested for cytomegalovirus (CMV) using real-time polymerase chain reaction. The results for 10 infants (3.8%, 95% confidence interval, 2.1–6.8) were found to be positive. Congenital CMV infection was not associated with any of the demographic or maternal factors including HIV. These data demonstrate the high prevalence of congenital CMV infection and the feasibility of CMV screening by real-time polymerase chain reaction testing. Key Words: congenital CMV, saliva PCR, newborn screening, developing country Accepted for publication August 28, 2014. From the *Centre for Healthy Start Initiative, Lagos, Nigeria; †Department of Pediatrics, Hennepin County Medical Center, University of Minnesota, Minneapolis, Minnesota; ‡Department of Pediatrics; and §Department of Microbiology, University of Alabama at Birmingham, Alabama. This study was supported by the National Institute on Deafness and Other Communication Disorders (N01 DC50008). The authors have no conflicts of interest to disclose. Address for correspondence: Suresh B. Boppana, MD, Departments of Pediatrics and Microbiology, University of Alabama at Birmingham, CHB 114, 1600, 7th Ave South, Birmingham, AL 35233. E-mail: [email protected]. Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s Web site (www.pidj.com). Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved. DOI: 10.1097/INF.0000000000000555
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C
ytomegalovirus (CMV) is a frequent cause of congenital infection and a leading nongenetic cause of permanent congenital or early-onset hearing loss (PCEHL) in children.1,2 Although limited data suggest high prevalence of congenital CMV (cCMV) infection in developing countries with high maternal CMV seroprevalence, the burden of disease and natural history of cCMV infection, especially in sub-Saharan Africa, have not been well defined.1,3–5 Additionally, the role of cCMV in PCEHL in the African continent has not been examined, although infants with microcephaly have been reported to be significantly at risk for PCEHL in Nigeria.6 Early identification of infants with cCMV allows for prompt detection of children at risk for PCEHL who require appropriate intervention during critical stages of language development.1,2 Real-time polymerase chain reaction (PCR) testing of newborn saliva has been shown to be highly specific and sensitive for detecting CMVinfected infants.7,8 We therefore conducted a pilot study to determine the prevalence of cCMV in an inner-city community in Lagos, Nigeria, with a previously reported high occurrence of PCEHL.9
METHODS Infants were enrolled in the study by convenient sampling of neonates on admission between November 2012 and April 2013 at Island Maternity Hospital (IMH) and Massey Children’s Hospital (MCH) in Lagos, Nigeria, whose mothers gave consent to participate in the study. Demographic data and medical history were obtained from hospital records and ethical approval from the Lagos State Government Health Service Commission. Dried saliva swabs were collected, labeled with a unique ID number and transported to the University of Alabama at Birmingham for testing by real-time PCR for CMV without the DNA extraction step as described.7,8 A sample was considered positive if one or more international units (IU) per reaction was detected. The detection limit of this PCR assay was determined to be 116 IU/mL of the sample (1.72 ge/ mL = 1 IU/mL) using the Acrometrix (Life Technologies, Grand Island, NY) CMV international standards. No follow-up visits were included, but parents were informed of the infant’s CMV status for further medical attention. HIV 1 and HIV 2 testing was routinely conducted during pregnancy using 2 rapid immunochromatographic screening test kits.9 Two negative or positive results are confirmatory for HIV status. Discordant results were resolved with enzyme-linked immunosorbent assay. Data were analyzed using SPSS statistical package version 21 (IBM Corp, Armonk, NY). To determine differences between infants with and without cCMV, we used a case-control sample in which infants with CMV were matched on the basis of gender to infants without CMV in the ratio of 1:10. Gender was selected as the matching criterion because of the potential confounding effect of the high frequency of glucose6-phosphate dehydrogenase deficiency in male infants in the study population. The controls were selected from infants with the closest dates of birth from the same hospital. Maternal age, ethnicity, gravidity, parity, mode of delivery, HIV status, multiple gestation, gestational age, birth weight, presence of neonatal jaundice and admission status were compared between CMV-infected and CMVuninfected infants. Statistical significance was determined by Pearson χ2 test or Fisher exact for categorical variables and student t test for continuous variables.
RESULTS Of the 263 infants tested, 10 (6 females and 4 males) were CMV positive, amounting to a prevalence rate of 3.8% (95% confidence interval: 2.1–6.9%). The prevalence of cCMV was not significantly different between the 2 hospitals: 3.4% (5 of 149) versus 4.4% (5 of 114). The characteristics of CMV-infected newborns are shown in Table 1. Mean age of mothers with CMV-infected babies © 2015 Wolters Kluwer Health
The Pediatric Infectious Disease Journal • Volume 34, Number 3, March 2015
Congenital CMV in Nigeria
TABLE 1. Characteristics of Infants with Congenital CMV Infection Status at Screening
Mother’s Age (years)
Mode of Delivery
Gestation
Gestational Age (weeks)
Birth Weight (kg)
1
Out-born
30
SVD
Singleton
39
Missing
2 3 4 5 6 7 8
Out-born Inborn Inborn Out-born Out-born Inborn Out-born
30 38 38 30 22 31 34
SVD SVD BREECH EMCS SVD EMCS EMCS
Singleton First twin Second twin One of triplet Singleton Singleton Singleton
39 31 31 38 39 37 30
Missing 1.0 1.0 Missing N 3.30 1.25
9 10
Inborn Inborn
21 23
EMCS EMCS
Singleton Singleton
39 37
3.75 2.90
Clinical Features Symptomatic: hepatosplenomegaly and bronchopneumonia Asymptomatic Asymptomatic, NNJ Asymptomatic, NNJ Asymptomatic Asymptomatic Asymptomatic, NNJ Symptomatic: hepatosplenomegaly and bronchopneumonia, and NNJ Asymptomatic Asymptomatic
SVD indicates spontaneous vertex delivery; EMCS, emergency caesarean delivery; NNJ, treated for jaundice.
was 29.7 ± 6.1 years (IMH: 30.2 ± 8.04; MCH: 29.2 ± 4.38 years). Mean gestational age for CMV-infected infants was 35.9 ± 4.0 weeks (IMH: 35.0 ± 3.74; MCH: 37.0 ± 3.94 weeks), with a mean birth weight of 2.2 ± 1.3 kg (IMH: 2.39 ± 1.30; MCH: 3.23 ± 1.06 kg). Of the infected children, 2 infants were symptomatic. Both infants had hepatosplenomegaly and bronchopneumonia, and 1 baby had neonatal jaundice also. Maternal HIV status was known for 162 infants including 8 congenitally infected children. The prevalence of maternal HIV infection was 4.9% (6 of 162), and none of the CMV-infected babies was born to a HIV-positive mother. There were no statistically significant differences between CMV-infected infants and their matched controls with respect to maternal age, ethnicity, gravidity, parity, gestational age, maternal HIV status and birth weight (see Table, Supplemental Digital Content 1, http:// links.lww.com/INF/C19).
DISCUSSION This study utilized a virologic assay that is reliable and convenient to identify CMV-infected newborns. By eliminating the requirement for DNA extraction, this PCR assay has significant cost savings also. The results from this population with near-universal seroimmunity demonstrated the high prevalence of cCMV and the feasibility of screening newborns by real-time PCR of dried-saliva swabs in resource-poor settings. The prevalence of cCMV in this study falls within the reported range of 0.9% (Mexico) and 5.4% (Gambia) for developing countries but well over 0.5–0.7% reported in developed countries.1,3–5 Our findings are consistent with those reported in a recent study from Zambia in which cCMV, based on the detection of CMV DNA in saliva, urine or sera or on the detection of serum CMV-IgM antibodies, was detected in 3.8% (15 of 395) of neonatal admissions in the first 3 weeks in a population with high maternal HIV prevalence.3 A study from the Gambia reported significantly higher prevalence of cCMV (5.4%, 40 of 741), which was associated with active placental malarial infection.4 Although CMV seroprevalence was not determined as part of this study, a previous study among pregnant women in Lagos, Nigeria, showed that 97.2% were CMVIgG positive.10 It is therefore likely that most women in our study were seroimmune before pregnancy. High prevalence (2.9%, 22 of 748) of cCMV in HIV-exposed infants was also documented in a recent study from South Africa.5 Compared with findings from Zambia and South Africa, none of the HIV-exposed infants was CMV-infected in our study.3,5 In the Zambian study, the prevalence of cCMV was 11.4% and 2.1% among neonates born to HIV-infected and HIV-uninfected mothers, respectively.3 In Western Cape, South Africa, 2.9% of infants born to 748 © 2015 Wolters Kluwer Health
HIV-infected mothers had cCMV.5 The prevalence of maternal HIV infection of 4.9% in our study population is consistent with previous data from this inner-city community.8 HIV-infection status was known for 162 mothers including 8 mothers with CMV-infected newborns, and none of the babies with cCMV was born to HIV-infected mothers. However, the number of women with HIV infection in this study is too small to determine the role of maternal HIV infection on intrauterine CMV transmission, and therefore, the association between cCMV and maternal HIV in this population merits further research. There were no associations between congenital CMV and maternal age, parity, mode of delivery, gestational age, birth weight, gender and jaundice. A major limitation of this study is the small sample size and the use of convenience sampling. Thus, it is not clear whether these data are representative of cCMV prevalence in the population in Nigeria. Additionally, infected children were not followed to document long-term outcomes. Although the real-time PCR assay has been shown to be highly specific in previous studies in the United States, it is possible that the rate of false-positive PCR results could be higher in populations with concurrent maternal infections.7,8 Nevertheless, the findings of this study underscore the need for a prospective newborn CMV screening study with longterm follow-up to document the natural history and disease burden of cCMV in this population. In addition, the utility of the real-time PCR assay should be evaluated in larger studies in such populations. It is crucial to examine the role of cCMV among infants with congenital, early-onset/late-onset, fluctuating and progressive sensorineural hearing loss to develop evidence-based guidelines for intervention advocacy for at-risk infants. Overall, this pilot study and the follow-up research should fill an important epidemiologic gap in the study of cCMV infection in sub-Saharan Africa.
ACKNOWLEDGMENTS We thank the management of IMH and Massey Street Children’s Hospital, Lagos, Nigeria, for their support in facilitating access to the participants in this study. REFERENCES 1. Manicklal S, Emery VC, Lazzarotto T, et al. The “silent” global burden of congenital cytomegalovirus. Clin Microbiol Rev. 2013;26:86–102. 2. Dahle AJ, Fowler KB, Wright JD, et al. Longitudinal investigation of hearing disorders in children with congenital cytomegalovirus infection. J Am Acad Audiol. 2000;11:283–290. 3. Mwaanza N, Chilukutu L, Tembo J, et al. High rates of congenital cytomegalovirus infection linked with maternal HIV infection among neonatal admissions at a large referral center in sub-Saharan Africa. Clin Infect Dis. 2014;58:728–735.
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4. van der Sande MA, Kaye S, Miles DJ, et al. Risk factors for and clinical outcome of congenital cytomegalovirus infection in a peri-urban West-African birth cohort. PLoS One. 2007;2:e492. 5. Manicklal S, van Niekerk AM, Kroon SM, et al. Birth prevalence of congenital cytomegalovirus among infants of HIV-infected women on prenatal antiretroviral prophylaxis in South Africa. Clin Infect Dis. 2014;58:1467–1472. 6. Olusanya BO. Risk of sensorineural hearing loss in infants with abnormal head size. Ann Afr Med. 2013;12:98–104. 7. Boppana SB, Ross SA, Shimamura M, et al; National Institute on Deafness and Other Communication Disorders CHIMES Study. Saliva polymerasechain-reaction assay for cytomegalovirus screening in newborns. N Engl J Med. 2011;364:2111–2118. 8. Ross SA, Ahmed A, Palmer AL, et al; for the National Institute on Deafness and Other Communication Disorders CHIMES Study. Detection of congenital cytomegalovirus infection by real-time polymerase chain reaction analysis of saliva or urine specimens. J Infect Dis 2014;210:1415–1418. 9. Olusanya BO, Afe AJ, Onyia NO. Infants with HIV-infected mothers in a universal newborn hearing screening programme in Lagos, Nigeria. Acta Paediatr. 2009;98:1288–1293. 10. Akinbami AA, Rabiu KA, Adewunmi AA, et al. Seroprevalence of cytomegalovirus antibodies amongst normal pregnant women in Nigeria. Int J Womens Health. 2011;3:423–428.
SUBACUTE OSTEOMYELITIS OF THE FEMUR DUE TO FUSOBACTERIUM NUCLEATUM IN A 7-YEAR-OLD BOY Emily Budd, BM,* David S. Johnson, MPhil,† Eva Thomas, PhD,‡ and Manish Sadarangani, DPhil*§ Abstract: Subacute hematogenous osteomyelitis is an insidious infection, which commonly has a delayed diagnosis. We describe the case of a 7-year-old boy with subacute osteomyelitis, which was initially considered to be a bone tumor. Infection should be considered in all cases of bone pain, especially in children, even in the absence of typical systemic features of inflammation. Key Words: anaerobic, bone, child, infection Accepted for publication August 28, 2014. From the *Department of Pediatrics, BC Children’s Hospital and University of British Columbia, Vancouver, BC, Canada; †Department of Orthopaedics, Stockport NHS Foundation Trust, Stepping Hill Hospital, Stockport, SK2 7JE, United Kingdom; ‡Division of Microbiology, Virology and Infection Control, Department of Pathology, Children’s and Women’s Health Centre of BC, Vancouver, BC, Canada; and §Department of Paediatrics, University of Oxford, Oxford, United Kingdom. The authors have no conflicts of interest or funding to disclose. Address for Correspondence: Dr Manish Sadarangani, Department of Paediatrics, University of Oxford, Level 2, Children’s Hospital, Oxford OX3 9DU, United Kingdom. E-mail: [email protected]. Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s website (www.pidj.com). Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved. DOI: 10.1097/INF.0000000000000558
CASE REPORT Subacute hematogenous osteomyelitis (AHO) is an insidious infection, which commonly has a delayed diagnosis. We describe the case of a 7-year-old boy with subacute osteomyelitis, which was initially considered to be a bone tumor. Infection should be considered in all cases of bone pain, especially in children, even in the absence of typical systemic features of inflammation. A previously healthy 7-year-old boy developed onset of pain in his left lower leg, predominantly in his knee. There was no definite history of trauma other than mild knocks while playing on a trampoline and wrestling with his brother approximately 1–2 days before onset of symptoms. During the next few weeks, he presented to 3 hospitals with episodes of increased pain. On each occasion it was felt he had a soft
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tissue injury and his symptoms subsequently eased but did not fully resolve. On the last occasion, when he had sustained a minor head injury requiring overnight admission, the knee pain was noted and radiographs taken were normal. He was afebrile with normal vital signs. No further investigations were ordered at that stage as he was otherwise well. Four weeks after the onset of his symptoms, he was referred to an orthopedic surgeon by his family doctor due to ongoing knee pain. He was well and afebrile, but had a limp holding the left knee flexed. He was tender throughout the lower limb but mostly over the lower thigh. There was no knee effusion and, when relaxed, there was full range of movement of the knee. There were no local signs of inflammation, with only a few nontender lymph nodes present in each groin. Radiographs of his hips and left knee and an ultrasound scan of the left hip were normal. A magnetic resonance scan showed a cystic lesion in the medial femoral condyle with associated bone bruising and a pathologic fracture, with involvement of the distal metaphysis. The lesion was suspected to be a chondroblastoma, although a clear cell chondrosarcoma was also considered. As the family moved to Canada from the UK a few days later, referral to the local oncology service at their destination was made. Shortly after the flight to Canada his pain greatly increased and he was admitted for further investigation of a presumptive bone malignancy. He had a temperature of 38.1°C and vital signs were otherwise normal. He had a knee effusion with marked tenderness and very limited range of motion in the hip, knee and ankle. Initial investigations revealed a normal white blood cell count (9.7 × 109/L) (neutrophils 5.6 × 109/L, lymphocytes 2.9 × 109/L) and platelet count (298 × 109/L), with a hemoglobin of 119 g/L and microcytosis (mean corpuscular volume 72.6 fL). The erythrocyte sedimentation rate was elevated (55 mm/h), as was the C-reactive protein (200 mg/L). The coagulation profile, lactate dehydrogenase, uric acid, renal and liver function tests were normal. One set of blood cultures was taken (one aerobic and one anaerobic bottle) and was subsequently negative. He was initially treated supportively with analgesia and anti-inflammatory drugs, but an increase in the swelling over the next 48 hours prompted an emergency arthotomy on the medial aspect of the knee. Purulent fluid was obtained under pressure from the distal femur, and therapy was commenced with cefazolin (100 mg/kg/d) postoperatively, as standard empiric therapy for osteoarticular infections. Four specimens were taken during surgery and transported to the laboratory in plain sterile containers, with all specimens being processed within 4 hours. White blood cells were seen on microscopy, with no organisms on Gram stain. Fusobacterium nucleatum was subsequently isolated from three specimens by culture and confirmed by 16S DNA sequencing, confirming the diagnosis of subacute osteomyelitis. He was treated with 2 weeks of intravenous clindamycin (40 mg/kg/d) and penicillin G (250,000 units/kg/d) followed by 4 weeks of oral clindamycin (30 mg/ kg/d), the organism being susceptible to these antibiotics. Dual therapy was used initially due to the longstanding nature of symptoms and to achieve good bactericidal effect, with ongoing therapy with clindamycin only due to its excellent bone penetration. Duration was guided by clinical response and review of the literature regarding pediatric Fusobacterium bone and joint infections. He made a full recovery with no residual pain, limb length discrepancy or growth plate disturbance at 2 years post-surgery.
DISCUSSION Osteomyelitis can be broadly categorized based on duration of symptoms into acute, subacute and chronic, although absolute cut-offs to separate these categories have not been defined. Chronic osteomyelitis is distinguished histologically by the presence of necrotic tissue and involucrum. Subacute osteomyelitis is a slowly progressive primary bone infection with symptoms taking over 2 weeks to develop.1 In contrast to AHO, there is usually no fever or leukocytosis in subacute © 2015 Wolters Kluwer Health
