Pediatric Pulmonology 50:E5–E7 (2015)

Case Report

Mycobacterium Avium Complex (MAC) Presenting as the First Infection in a Child With Cystic Fibrosis Andrew Colin,

MD,*

Elisa Basora, MD, and Shatha Yousef,

MD

Summary. Nontuberculous mycobacteria (NTM) have been increasingly recognized in recent years as contributors to clinically significant lung infection in cystic fibrosis (CF) patients. Reports of prevalence vary from 6 to 22% around the world. Prevalence estimates in childhood CF is challenging since sputum producers are rare, bronchoalveolar lavage is an invasive procedure and may not be feasible, and mounting evidence deeming throat cultures to be unsuccessful in detecting NTM. We report a case of an overall healthy 13 year old young adolescent female with CF, who presented with Mycobacterium avium complex (MAC) as her first documented lung infection, and while only presenting with minor cough proved to have severe purulent bronchial infection. Contrary to common paradigms, NTM can be the first infection in a non-previously infected airway, and, this first infection can be of a serious nature unlike the more subtle anticipated pattern. The causes of the high and probably increasing overall incidence of NTM and specifically in CF elude explanation and mandate further study. Continuing efforts should be invested into the study of all aspects of this ominous infection. Pediatr Pulmonol. 2015;50:E5–E7. ß 2014 Wiley Periodicals, Inc.

Key words: Cystic fibrosis (CF). Funding source: none reported.

Nontuberculous mycobacteria (NTM) are increasingly acknowledged as contributors to significant lung infection in cystic fibrosis (CF). Reports of prevalence vary from 6 to 22% worldwide.1,2 While prevalence in adults can be estimated with some accuracy, childhood CF estimates are a challenge since valid cultures can only be obtained from rare sputum producers, or from bronchoalveolar lavage. We recently attempted to grow NTM from throat cultures but were predictably unsuccessful3 supporting the reported UK experience. Most reports of NTM in CF patients suggest it to affect patients with previous infections and declined pulmonary functions.2 A recent paper suggests that it is likely safe to withhold treatment until clinical signs develop.1 We report herein a case of a healthy adolescent female with CF, presenting with Mycobacterium avium complex (MAC) as her first documented lung infection, and while only with minor cough, proved to have severe purulent bronchial infection.

pancreatic sufficiency. Her older sister’s CF led to her diagnosis. She had no previous lung involvement. A chest CT scan at age 7 was normal (Fig. 1A) and biannual chest radiographs remained unchanged. Throat cultures performed 3–4 times/year were consistently negative. A surveillance bronchoscopy at age 10, performed when she underwent cholecystectomy for cholelithiasis, revealed all negative cultures including mycobacteria. A differential cytology from the right lung revealed: Neutrophils: 16%, Lymphocytes: 6%,

Department of Pediatric Pulmonology School of Medicine, University of Miami, Miller, Florida. Conflict of interest: The authors have no potential conflict of interest. 

Correspondence to: Andrew Colin, MD, University of Miami/Miller School of Medicine 1580 NW 10th Ave, Miami, FL, 33136. E-mail: [email protected] Received 27 March 2014; Accepted 25 July 2014.

CASE REPORT

The patient was a 13 year old with compound heterozygous delta F508/P67L CFTR mutations and ß 2014 Wiley Periodicals, Inc.

DOI 10.1002/ppul.23101 Published online 8 September 2014 in Wiley Online Library (wileyonlinelibrary.com).

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Fig. 1. (A) Chest CT scan (2010) revealing normal parenchyma with no evidence of structural changes. (B) Follow up CT (2013) with lingular infiltrate (C) Initial bronchoscopy with the noted CXR changes revealing purulent secretions emanating from the lingual. (D) Follow up bronchoscopy many months after treatment with erythematous and inflamed lingular mucosa. Arrows pointing to lingular orifice.

Histiocytes: 78% with comparable results from the left lung. At age 13 she developed a minor cough and nasal congestion, without fever, sputum production, sinus pain, or headaches. Spirometry remained normal and unchanged. Chest radiograph (CXR) revealed a lingular infiltrate. Induced sputum grew exclusively MAC. Baronchoscopy revealed normal appearing airways with the stark exception of the lingular bronchus that was overflowing with purulent secretions (Fig. 1C) and grew MAC with sensitivities identical to the sputum obtained culture. Subsequently, triple oral therapy was started. She continued to be asymptomatic; however her CXR and a CT scan 6 months into the course (Fig. 1B) remained abnormal. Repeat bronchoscopy revealed improvement albeit not complete normalization of the lingular bronchus with persistent erythema (Fig. 1D). This case raises important points related to NTM in CF patients. It expands our limited insight of the natural history of this infection. To our knowledge our patient is the first reported with NTM infection in an infectionnaı¨ve CF lung. As such it alerts physicians treating children with CF, that contrary to common paradigms,1,2 NTM may be the first organism isolated in a previously culture negative airway, and as a first isolated organism, Pediatric Pulmonology

can be of a serious nature as opposed to the anticipated insidious pattern. The high and probably increasing overall incidence of NTM specifically in CF4 eludes explanation and mandates further study. A recent pilot study from Florida detected a prevalence of 9.4% of NTM in the pediatric CF population of two centers.3 Considering the limited diagnostic ability for children, this number approaches the overall prevalence of 13% in US CF populations over age 10 reported by Olivier et al.2 This patient being a Florida resident, together with the relatively high incidence of NTM in children in Florida suggested by Yousef et al.3 point to previous assumption of an increased NTM incidence in warmer climates.4 Air-conditioning use in hot and humid climates has been speculated to possibly concentrate and spread NTM. Moreover, higher surface waters may serve as one of the main environmental sources of mycobacteria.5 That said, recent reports point to increased NTM infections including chillier regions such as an outbreak of Mycobacterium abscessus in CF patients in Calgary, Alberta (Harvey Rabin, MD— personal communication). Our patient’s older sister, who lives in a different state, has recently been infected with M. abscessus. Polymorphisms or mutations in the CFTR gene have been suggested as susceptibility factors for MAC infections; e.g., variations including poly-T, TG repeats, and M470V appear to play a role in susceptibility to pulmonary MAC infections. While admittedly speculative, the infection of the two sisters by different acid-fast-bacilli may point to an increased vulnerability to NTM by virtue of their shared rare P67L mutation.6,7 The predominantly lingular involvement with MAC in non-CF elderly females dubbed “Lady Windermere Syndrome” is well described, with speculation of habitual and voluntary cough suppression being the underlying etiology. Our patient’s young age, though with interestingly similar clinical features, separates her from the distinctive age of this observed population. In sum, it appears that the encroaching and potentially disastrous outbreak of NTM in CF patients includes children, primary infection, and uncommon circumstances. Continuing efforts should be invested into the study of all aspects of this ominous infection. REFERENCES 1. Martiniano SL, Sontag MK, Daley CL, Nick JA, Sagel SD. Clinical significance of a first positive nontuberculous mycobacteria culture in cystic fibrosis. Ann Am Thorac Soc 2013;11:36– 44. 2. Olivier KN, Weber DJ, Wallace RJ Jr, Faiz AR, Lee JH, Zhang Y, Brown-Elliot BA, Handler A, Wilson RW, Schechter MS, et al. Nontuberculous mycobacteria. I: multicenter prevalence study in cystic fibrosis. Am J Respir Crit Care Med 2003;167:828–834. 3. Yousef S, Baker SP, Della D, Volpe A, Colin A, Quizon A. Prevalence of non-tuberculous mycobacteria (NTM) in pediatric

MAC as a First Infection in a Child With CF patients with cystic fibrosis (CF) in Florida – a two center study. Paediatr Respir Rev 2013;14(Suppl 2):S72. 4. Leung JM, Olivier KN. Nontuberculous mycobacteria: the changing epidemiology and treatment challenges in cystic fibrosis. Curr Opin Pulm Med 2013;19:662–669. 5. Adjemian J, Olivier KN, Seitz AE, Falkinham JO 3rd, Holland SM, Prevots DR. Spatial clusters of nontuberculous mycobacterial lung disease in the United States. Am J Respir Crit Care Med 2012;186:553–558.

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6. Jang MA, Kim SY, Jeong BH, Park HY, Jeon K, Kim JW, Ki CS, Koh WJ. Association of CFTR gene variants with nontuberculous mycobacterial lung disease in a Korean population with a low prevalence of cystic fibrosis. J Hum Genet 2013;58:298–303. 7. Mai HN, Hijikata M, Inoue Y, Suzuki K, Sakatani M, Okada M, Kimura K, Kobayashi N, Toyota E, Kudo K, et al., Pulmonary Mycobacterium avium complex infection associated with the I VS8-T5 allele of the CFTR gene. Int J Tuberc Lung Dis 2007;11:808–813.

Pediatric Pulmonology

Mycobacterium avium complex (MAC) presenting as the first infection in a child with cystic fibrosis.

Nontuberculous mycobacteria (NTM) have been increasingly recognized in recent years as contributors to clinically significant lung infection in cystic...
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