CASE
REPORTS
Rhizopus Osteomyelitis A Case Report and Review
ROGER M. ECHOLS. M.D. DANIEL S. SELINGER. M.D. CHRISTIAN HALLOWELL. M.D.* IAMES
S. GOODWIN,
MARILYN
M.D.
H. DUNCAN,
M.D. ALICE H. CUSHING. M.D. Albuquerque, New Mexico
Mucormycosis osteomyelitis has previously been described exclusively in association with contiguous infections of rhinocerebral mucormycosis. In a patient with corticosteroid-dependent neutropenia and anemia osteomyelitis of the femur developed caused by the Mucoraceae Rhizopus. Although a primary focus was not identified, we believe this infection was hematogenous in origin. Mitogen stimulation to phytohemagglutinin (PHA) of the patient’s lymphocytes revealed depressed cellular immunity; however, there was specific response to Rhizopus extract. Treatment with systemic amphotericin B prevented further progression of the infection. A review of mucormycosis osteomyelitis is presented. Mycotic osteomyelitis is generally associated with disseminated blastomycosis [l], coccidioidomycosis [z] and cryptococcosis [3]. Candida and Aspergillus infections, although of increasing importance in the immunocompromised host, are rarely associated with mycotic osteomyelitis [4]. Disseminated histoplasmosis commonly results in metastatic foci in the bone marrow, however, without demonstrable osteomyelitis [5]. Osteomyelitis caused by the zygomycetes has previously been reported onlv in association with contiguous rhinocerebra1 mucormycosis infection. The following is a report of a case we believe to represent hematogenous osteomyelitis due to the Mucoraceae Rhizopus. CASE REPORT
From the Departments of Medicine and Pediatrics, Bernalillo County Medical Center, University of New Mexico School of Medicine; and the Medical Service, Veterans Administration Hospital, Albuquerque, New Mexico. Requests for reprints should be addressed to Dr. Roger Echols, Division of Infectious Diseases, Department of Medicine, Bernalillo County Medical Center, Albuquerque, New Mexico 87131. Manuscript accepted June 30.1978. * Present address: Public Health Service Indian Hospital, Tuba City, Arizona 86045.
This 18 year old girl had presented at age 6 with anemia secondary to erythroid hypoplasia. She was treated with corticosteroids for two years with resolution of the anemia. At age 9 neutropenia with granulocyte hypoplasia developed for which, from age 10 years to the present, she has received varying doses of prednisone. Despite the corticosteroid therapy, she suffered periodic episodes of neutropenia associated with lymphadenitis, pneumonia and sinusitis. In 1976 oxymetholonc was added to the treatment regimen, but intermittent neutropenia continued to be a problem. In June 1977, during recovery from an episode of neutropenia and pneumonia of undetermined etiology, the patient first complained of pain in the right hip. Roentgenograms of the hip disclosed no abnormalities. A diagnosis of trochanteric bursitis was made, and the bursa was injected with lidocaine. Gram stains and bacterial cultures of material subsequently aspirated from the right hip were negative. Fungal cultures were not performed. The patient never had a fever, but hip pain recurred shortly after the first symptoms, when lytic lesions appeared in the neck and greater trochanter of the right femur (Figure I]. A second bone scan showed increased activity in the same area. A needle biopsy specimen of the right femoral neck was interpreted as showing chronic osteomyelitis with broad, branching, nonseptate
January 1979 The American Journal of Medicine
Volume 66
141
RHIZOPLJS OSTEOMYELITIS-ECHOLS
ET AL
hyphae in the tissue (Figure 2). Bacterial cultures were negative, but fungal cultures grew Rhizopus species [6]. Mean in-
hibitory concentrations of amphotericin B for the isolate were less than 0.1 rg/ml by Miiller-Hinton agar dilution technic 171.
A search for other foci of Rhizopus infection was inconclusive. Roentgenographic changes compatible with chronic sinusitis were unchanged from those on roentgenograms taken 16 months earlier, and the sinus was not aspirated. Because of severe osteoporosis and the prolonged immobility necessitated by debridement, surgery was not undertaken. The patient was treated with systemic amphotericin B, and theprednisone dose was reduced to physiologic levels. After two months of therapy, roentgenograms showed a compression fracture of the femoral neck. Surgical intervention was prohibited at that time by recurrent severe neutropenia. In December 1977. after a total dose of 1.7 g, amphotericin B therapy was discontinued because of severe systemic reactions. At the time of this report, the patient has received no amphotericin for six months. She has returned to school and ambulates with crutches. Repeat bone scans and roentgenograms have shown no progression of the disease. TEST OF IN VITRO REACTIVITY
lytic lesions femur.
involving
the neck and shaft of the right
MITOGEN
AND
ANTIGEN
The patient’s peripheral blood mononuclear cells were twice evaluated for in vitro response to PHA and to a saline extract of Rhizopus, before and after four months of amphotericin B therapy. Peripheral venous blood was obtained after the patient had not received any medications for 48 hours. Mononuclear cells were separated and cultured as previously described [8]. The patient’s cells were assayed in parallel with cells from two age and sex-matched normal subjects. On both occasions,
Figure 2. Hematoxylin and eosin stain of biopsy material from right femur. Osteomyelitis with broad branching nonseptate hyphae are present. Magnification X 625.
142
January 1979
The American Journal of Medicine
Volume 66
RHIZOPUS OSTEOMYELITIS-ECHOLS
the patient’s cells manifested a depressed response to four concentrations of PHA compared to that of the control subjects [Table I). The response of the patient’s cells was from 2 to 45 per cent of the mean response of the control subjects, depending on the concentration of PHA employed. However, the patient’s peripheral blood mononuclear cells were stimulated on both occasions by a Rhizopus extract, whereas cells from the four control subjects were not. COMMENTS Fungi of the family Mucoraceae, ubiquitous in nature, include the genera Absidia, Mucor, Rhizopus and Cunninghamella which account for invasive disease in the immunocompromised host [9]. Although they can infect any organ system, three distinct clinical entities have been described in association with the Mucoraceae. Rhinocerebral mucormycosis, commonly associated with diabetic ketoacidosis, has originated in the nasal mucosa and spread directly or through blood vessels to the sinuses, orbit and brain [lO,ll]. Acidotic states associated with renal failure or severe diarrhea have also been implicated as predisposing factors [12]. This form of infection has been successfully treated with correction of the underlying metabolic disorder, systemic administration of amphotericin B and surgical debridement [lo-121. Untreated, eventually fatal, cases of rhinocerebral mucormycosis have been associated with hematogenous spread to the brain, lungs, spleen, kidneys, liver and other organs [12,13]. Primary pulmonary mucormycosis has occurred most frequently in immunosuppressed leukopenic patients with underlying myeloproliferative or reticuloendothelial malignancy in relapse [14,15]. Corticosteroid and/or broad-spectrum antibiotic therapy has been implicated as a contributing factor. Pulmonary mucormycosis has usually been fatal unless a remission in the underlying malignancy could be achieved [la]. One adult patient with pulmonary mucormycosis complicating acute lymphocytic leukemia was successfully treated with amphotericin B and discontinuation of immunosuppressive agents [16]. A third form of mucormycosis, invasion of the gastrointestinal tract, has characteristically affected the terminal ileum, cecum and colon, primarily in children with malnutrition and amebic colitis [17]. Osteomyelitis due to mucoraceae has been previously described only in association with a contiguous tissue infection. Altschtiler and Wadleigh [18]reported osteomyelitis of the maxillary sinus caused by Rhizopus niger in an insulin-dependent diabetic patient with rhinocerebral mucormycosis. Treatment, consisting of radical dissection and amphotericin B, was successful. Similarly, Kaufman and Stone [19] reported a case of osteomyelitis involving the frontal bone of a previously
January
TABLE I
ET AL.
Response to Phytohemagglutinin and Rhizopus of Peripheral Blood Mononuclear Cells from the Patient and Controls Patient’ Before Rx
Aner Rx
130 316 304 2,246 11,406
176 1,082 1,604 6,680 16,765
496 7,873 16,394 31,363 37,414
395 369 455 578 1,052
1,298
3,042 2,986 3,106 3,021 2,912 3,017 2,923
Controls
Phytohemagglutinin 0 0.2 0.4 2.0 4.0 Rhiropust0 1/10,000 l/l,000 l/100 l/5 l/2 Undiluted
.
1,949 2,617 3,070
f 192 f 5,166 f 7,604 f 13,679 f 15,528 f f f f f f f
718 724 816 690 503 755 867
Data for the patient are given as the mean counts per minute of sextuplicate cultures at four concentrations of PHA in 72 hour cultures. The patient was assayed before (September 1977) and after (February 1978) amphotericin B therapy. The data for controls are given as mean f standard deviation of the mean responses for 12 control subjects. The background counts per minute have not been subtracted from the data. 7 Peripheral blood mononuclear cells, 5 X lo5 in 200 ~1 were cultured in microtiter plates with various dilutions of the Rhizopus extract (protein concentration 2.0 mg/ml) for 160 hours and were pulsed with tritiated thymidine (5 X 10V7 Ci/well) at 148 hours. The data for controls are given as mean standard deviation of the mean response for four control subjects. Background counts per minute have not been subtracted. l
undiagnosed diabetic patient with rhinocerebral mucormycosis. Again, surgical debridement and amphotericin B therapy were successful in achieving cure. Roentgenologic changes of osteomyelitis were described in two additional fatal cases of rhinocerebral mucormycosis [20]. Hematogenous dissemination to the bone marrow without osteomyelitis has also been reported. Martin et al. [21] described bone marrow dissemination in a previously healthy two and a half month old infant in whom rhinocerebral mucormycosis developed after a severe bout of diarrhea. The infant rapidly succumbed, and autopsy revealed metastatic foci in the lungs, pleura, esophagus, meninges, pancreas and bone marrow. Osteomyelitis was not described. In a subsequent report of disseminated mucormycosis in a patient with acute granulocytic leukemia, autopsy revealed widespread organ involvement in which bone marrow and blood vessel invasion were apparent, but histologic changes of osteomyelitis were not [22]. The diagnosis of Rhizopus osteomyelitis in our patient was established by roentgenographic, microbiologic and histologic criteria. The presence of tissue invasion by
1676
The American
Journal of Medicine
Volume 66
143
RHIZOPUS OSTEOMYELITIS-ECHOLS
ET AL.
broad, branching, nonseptate hyphae was corroborated by the growth of Rhizopus species from the biopsy material. Blood vessel invasion, considered by some as a requisite for the diagnosis of mucoraceae infection [12], was not observed in the small amount of biopsy material available for microscopic examination. This case of Rhizopus osteomyelitis is unusual in several respects. The source of infection is unknown. The patient had preceding infections of the paranasal sinuses and a pulmonary infection which resolved without establishment of an etiologic agent. Either of these could have been the site from which dissemination occurred. The relapsing and remitting nature of the underlying hematologic disorder may have permitted its coexistence with Rhizopus infection of the respiratory tract without preventing hematogenous spread to the femur. We have assumed that the bone involvement occurred hematogenously, not only because of the absence of any contiguous infection, but also because the bone involved, the femoral metaphysis, is a characteristic site for hematogenous osteomyelitis in this age group [23]. Although both the bursa and the joint space of the right hip were penetrated by needles prior to biopsy, there was no evidence of subsequent infection in either of those sites. The in vitro mitogen studies suggest that the patient had a defect in cell-mediated immunity, although it is not known whether this contributed to, or resulted from, the chronic fungal infection. Stobo et al. [24,25] have described several patients with chronic fungal infections and depressed cellular immunity in whom the depression was mediated by suppressor cells which did not remit when the patient’s clinical conditions improved. In our case, the patient’s response to PHA improved
somewhat after she received a course of amphotericin B therapy, but the response was still less than 50 per cent of control (Table I]. The patient’s lymphocytes did, however, respond in vitro to a saline extract of Rhizopus, whereas the lymphocytes from four control subjects did not. Thus, the patient was apparently able to mount a cell-mediated immune response to the infecting organism, although the magnitude of that response (stimulation index 2-3) was far less than that obtained by incubation of lymphocytes from normal subjects with fungal antigens to which the donors have been previously exposed (stimulation index >20). The low grade immune response may have contributed to the chronicity and local containment of this rare infection. Treatment of mucormycosis osteomyelitis has been largely empiric. In the reported cases of contiguous osteomyelitis, the patients have been managed with surgical debridement and amphotericin B therapy as well as treatment of the underlying disease. This is similar to the experience with other types of mycotic osteomyelitis [3]. Our patient, after receiving more than 1.7 g of amphotericin B, presently has no evidence of progression of the infection. Although surgical curettage may be necessary for complete resolution, technical difficulties resulting from corticosteroid-induced osteopenia and recurrent neutropenia have prevented this treatment modality. ACKNOWLEDGMENT
We gratefully acknowledge the assistance of Carol Dudley, MS., and John Ulrich, Ph.D., of the Microbiology Laboratory of Bernalillo County Medical Center for identification and amphotericin B sensitivities of the Rhizopus organism.
REFERENCES 1. Busey JF: Blastomycosis I. A review of 198 collected cases
from Veterans Administration Hospitals. Am Rev Respir Dis 89: 659, 1964. 2. Iger M: Coccidioidomycosis osteomyelitis. Coccidioidomycosis (Ajello JD), Miami Symposia Specialists, 1977, p 177. 3. Rhangos WC, Chick EW: Mycotic infections of bone. South Med J 57: 664.1964. 4. Simoson MB. Merz WG. Kurlinski IP. et al.: Onoortunistic mycotic osteomyelitis: bone infections due to aspergillus *and candida species. Medicine (Baltimore) 56: 475, 1977. 5. Reddy P, Gorelick DF, Brasher CA, et al.: Progressive disseminated histonlasmosis as seen in adults. Am I Med 48: 629.1970.
January 1979
10.
11.
12. 13.
*
6. Moss SE, McQuown AL: Atlas of Medical Mycology, 3rd ed. Baltimore, Williams & Wilkins Co., 1969, p 167. 7. Gold W, Stout HA, Pagan0 JF. et al.: Amphotericin A and B, antifungal antibiotics produced by a streptomycetes. Antibiotics Annual 1955-1956. New York. Medical EncvcloI pedia, Inc., 1956, p 579. a. Goodwin JS, Messner RP, Bankhurst AD: Suppression of human T-cell mitoaenesis bv orostaelandin: existence of a prostaglandin producing suppressoy cell. J Exp Med 146: 1719.1977.
144
9.
The American Journal of Medicine
14. 15. 16. 17.
Emmons CW, Binford CH, Utz JP, et al.: Medical Mycology, Philadelphia, Lea & Febiger, 1977, p 254. Abramson E, Wilson D, Arky R: Rhinocerebral Phycomycosis in association with diabetes ketoacidosis. Report of two cases and a review of clinical and experimental experience with amphotericin B therapy. Ann Intern Med 66: 735, 1967. Pillsbury HC, Fischer ND: Rhinocerebral mucormycosis. Arch Otolarvnnol 103: 600. 1977. Meyer RD, Arem&ong D: Mucormycosis-changing status. CRC Crit Rev Clin Lab Sci 4: 42.1973. McBride RA, Corson JM, Dammin GJ: Mucormycosis. Two cases of disseminated disease with cultural identification of rhizopus; review of literature. Am J Med 28: 832, 1960. Meyer RD, Rosen P, Armstrong D: Phycomycosis complicating leukemia and lymphoma. Ann Intern Med 77: 871, 1972. Baker RD: The phycomycosis. Ann NY Acad Sci 174: 592, 1970. Medoff G, Kobayashi G: Pulmonary mucormycosis. N Engl J Med 286: 86,1972. Calle S, Klatsky S: Intestinal phycomycosis (Mucormycosis). Am J Chn Path01 45: 264,1966.
Volume 66
RHIZOPUS
18.
Altschiiler G, Wadleigh J: Cephalic phycomycosis (Rhizopus species). Ariz Med 29: 322,1972. 19. Kaufman RS, Stone G: Osteomyelitis of frontal bone secondary to mucormycosis. NY State J Med 73: 1325,1973. 20. Becker MH, Ngo N, Beranbaum SL: Mycotic infection of the paranasal sinuses. Radiology 96: 49, 1968. 21. Martin FP, Lukeman JM, Ranson RF, et al.: Mucormycosis of the central nervous system associated’with thrombosis of the internal carotid artery. J Pedlatr 44: 437,1954. 22. Meyer RD. Kaplan MH, Ong M. et al.: Cutaneous lesions in
OSTEOMYELITIS-ECHOLS
ET AL.
disseminated mucormycosis. JAMA 225: 737, 1973. 23. Waldvogel FA, Medoff G, Swartz MN: Osteomyelitis. A review of clinical features, therapeutic considerations and unusual aspects. N Engl J Med 282: 198, 1970. 24. Stobo JD, Paul 6, Van Scoy RE. et al.: Suppressor thymusderived lymphocytes in fungal infection. 1Clin Invest 57: 319.1976.
25.
January 1979
Stobo JD: Immunosuppression in man: suppression by macrophages can be mediated by interactions with regulatory T-cells. J Immunol 119: 918,1977.
The American Journal of Medicine
Volume 66
145
REPORTS
Rhizopus Osteomyelitis A Case Report and Review
ROGER M. ECHOLS. M.D. DANIEL S. SELINGER. M.D. CHRISTIAN HALLOWELL. M.D.* IAMES
S. GOODWIN,
MARILYN
M.D.
H. DUNCAN,
M.D. ALICE H. CUSHING. M.D. Albuquerque, New Mexico
Mucormycosis osteomyelitis has previously been described exclusively in association with contiguous infections of rhinocerebral mucormycosis. In a patient with corticosteroid-dependent neutropenia and anemia osteomyelitis of the femur developed caused by the Mucoraceae Rhizopus. Although a primary focus was not identified, we believe this infection was hematogenous in origin. Mitogen stimulation to phytohemagglutinin (PHA) of the patient’s lymphocytes revealed depressed cellular immunity; however, there was specific response to Rhizopus extract. Treatment with systemic amphotericin B prevented further progression of the infection. A review of mucormycosis osteomyelitis is presented. Mycotic osteomyelitis is generally associated with disseminated blastomycosis [l], coccidioidomycosis [z] and cryptococcosis [3]. Candida and Aspergillus infections, although of increasing importance in the immunocompromised host, are rarely associated with mycotic osteomyelitis [4]. Disseminated histoplasmosis commonly results in metastatic foci in the bone marrow, however, without demonstrable osteomyelitis [5]. Osteomyelitis caused by the zygomycetes has previously been reported onlv in association with contiguous rhinocerebra1 mucormycosis infection. The following is a report of a case we believe to represent hematogenous osteomyelitis due to the Mucoraceae Rhizopus. CASE REPORT
From the Departments of Medicine and Pediatrics, Bernalillo County Medical Center, University of New Mexico School of Medicine; and the Medical Service, Veterans Administration Hospital, Albuquerque, New Mexico. Requests for reprints should be addressed to Dr. Roger Echols, Division of Infectious Diseases, Department of Medicine, Bernalillo County Medical Center, Albuquerque, New Mexico 87131. Manuscript accepted June 30.1978. * Present address: Public Health Service Indian Hospital, Tuba City, Arizona 86045.
This 18 year old girl had presented at age 6 with anemia secondary to erythroid hypoplasia. She was treated with corticosteroids for two years with resolution of the anemia. At age 9 neutropenia with granulocyte hypoplasia developed for which, from age 10 years to the present, she has received varying doses of prednisone. Despite the corticosteroid therapy, she suffered periodic episodes of neutropenia associated with lymphadenitis, pneumonia and sinusitis. In 1976 oxymetholonc was added to the treatment regimen, but intermittent neutropenia continued to be a problem. In June 1977, during recovery from an episode of neutropenia and pneumonia of undetermined etiology, the patient first complained of pain in the right hip. Roentgenograms of the hip disclosed no abnormalities. A diagnosis of trochanteric bursitis was made, and the bursa was injected with lidocaine. Gram stains and bacterial cultures of material subsequently aspirated from the right hip were negative. Fungal cultures were not performed. The patient never had a fever, but hip pain recurred shortly after the first symptoms, when lytic lesions appeared in the neck and greater trochanter of the right femur (Figure I]. A second bone scan showed increased activity in the same area. A needle biopsy specimen of the right femoral neck was interpreted as showing chronic osteomyelitis with broad, branching, nonseptate
January 1979 The American Journal of Medicine
Volume 66
141
RHIZOPLJS OSTEOMYELITIS-ECHOLS
ET AL
hyphae in the tissue (Figure 2). Bacterial cultures were negative, but fungal cultures grew Rhizopus species [6]. Mean in-
hibitory concentrations of amphotericin B for the isolate were less than 0.1 rg/ml by Miiller-Hinton agar dilution technic 171.
A search for other foci of Rhizopus infection was inconclusive. Roentgenographic changes compatible with chronic sinusitis were unchanged from those on roentgenograms taken 16 months earlier, and the sinus was not aspirated. Because of severe osteoporosis and the prolonged immobility necessitated by debridement, surgery was not undertaken. The patient was treated with systemic amphotericin B, and theprednisone dose was reduced to physiologic levels. After two months of therapy, roentgenograms showed a compression fracture of the femoral neck. Surgical intervention was prohibited at that time by recurrent severe neutropenia. In December 1977. after a total dose of 1.7 g, amphotericin B therapy was discontinued because of severe systemic reactions. At the time of this report, the patient has received no amphotericin for six months. She has returned to school and ambulates with crutches. Repeat bone scans and roentgenograms have shown no progression of the disease. TEST OF IN VITRO REACTIVITY
lytic lesions femur.
involving
the neck and shaft of the right
MITOGEN
AND
ANTIGEN
The patient’s peripheral blood mononuclear cells were twice evaluated for in vitro response to PHA and to a saline extract of Rhizopus, before and after four months of amphotericin B therapy. Peripheral venous blood was obtained after the patient had not received any medications for 48 hours. Mononuclear cells were separated and cultured as previously described [8]. The patient’s cells were assayed in parallel with cells from two age and sex-matched normal subjects. On both occasions,
Figure 2. Hematoxylin and eosin stain of biopsy material from right femur. Osteomyelitis with broad branching nonseptate hyphae are present. Magnification X 625.
142
January 1979
The American Journal of Medicine
Volume 66
RHIZOPUS OSTEOMYELITIS-ECHOLS
the patient’s cells manifested a depressed response to four concentrations of PHA compared to that of the control subjects [Table I). The response of the patient’s cells was from 2 to 45 per cent of the mean response of the control subjects, depending on the concentration of PHA employed. However, the patient’s peripheral blood mononuclear cells were stimulated on both occasions by a Rhizopus extract, whereas cells from the four control subjects were not. COMMENTS Fungi of the family Mucoraceae, ubiquitous in nature, include the genera Absidia, Mucor, Rhizopus and Cunninghamella which account for invasive disease in the immunocompromised host [9]. Although they can infect any organ system, three distinct clinical entities have been described in association with the Mucoraceae. Rhinocerebral mucormycosis, commonly associated with diabetic ketoacidosis, has originated in the nasal mucosa and spread directly or through blood vessels to the sinuses, orbit and brain [lO,ll]. Acidotic states associated with renal failure or severe diarrhea have also been implicated as predisposing factors [12]. This form of infection has been successfully treated with correction of the underlying metabolic disorder, systemic administration of amphotericin B and surgical debridement [lo-121. Untreated, eventually fatal, cases of rhinocerebral mucormycosis have been associated with hematogenous spread to the brain, lungs, spleen, kidneys, liver and other organs [12,13]. Primary pulmonary mucormycosis has occurred most frequently in immunosuppressed leukopenic patients with underlying myeloproliferative or reticuloendothelial malignancy in relapse [14,15]. Corticosteroid and/or broad-spectrum antibiotic therapy has been implicated as a contributing factor. Pulmonary mucormycosis has usually been fatal unless a remission in the underlying malignancy could be achieved [la]. One adult patient with pulmonary mucormycosis complicating acute lymphocytic leukemia was successfully treated with amphotericin B and discontinuation of immunosuppressive agents [16]. A third form of mucormycosis, invasion of the gastrointestinal tract, has characteristically affected the terminal ileum, cecum and colon, primarily in children with malnutrition and amebic colitis [17]. Osteomyelitis due to mucoraceae has been previously described only in association with a contiguous tissue infection. Altschtiler and Wadleigh [18]reported osteomyelitis of the maxillary sinus caused by Rhizopus niger in an insulin-dependent diabetic patient with rhinocerebral mucormycosis. Treatment, consisting of radical dissection and amphotericin B, was successful. Similarly, Kaufman and Stone [19] reported a case of osteomyelitis involving the frontal bone of a previously
January
TABLE I
ET AL.
Response to Phytohemagglutinin and Rhizopus of Peripheral Blood Mononuclear Cells from the Patient and Controls Patient’ Before Rx
Aner Rx
130 316 304 2,246 11,406
176 1,082 1,604 6,680 16,765
496 7,873 16,394 31,363 37,414
395 369 455 578 1,052
1,298
3,042 2,986 3,106 3,021 2,912 3,017 2,923
Controls
Phytohemagglutinin 0 0.2 0.4 2.0 4.0 Rhiropust0 1/10,000 l/l,000 l/100 l/5 l/2 Undiluted
.
1,949 2,617 3,070
f 192 f 5,166 f 7,604 f 13,679 f 15,528 f f f f f f f
718 724 816 690 503 755 867
Data for the patient are given as the mean counts per minute of sextuplicate cultures at four concentrations of PHA in 72 hour cultures. The patient was assayed before (September 1977) and after (February 1978) amphotericin B therapy. The data for controls are given as mean f standard deviation of the mean responses for 12 control subjects. The background counts per minute have not been subtracted from the data. 7 Peripheral blood mononuclear cells, 5 X lo5 in 200 ~1 were cultured in microtiter plates with various dilutions of the Rhizopus extract (protein concentration 2.0 mg/ml) for 160 hours and were pulsed with tritiated thymidine (5 X 10V7 Ci/well) at 148 hours. The data for controls are given as mean standard deviation of the mean response for four control subjects. Background counts per minute have not been subtracted. l
undiagnosed diabetic patient with rhinocerebral mucormycosis. Again, surgical debridement and amphotericin B therapy were successful in achieving cure. Roentgenologic changes of osteomyelitis were described in two additional fatal cases of rhinocerebral mucormycosis [20]. Hematogenous dissemination to the bone marrow without osteomyelitis has also been reported. Martin et al. [21] described bone marrow dissemination in a previously healthy two and a half month old infant in whom rhinocerebral mucormycosis developed after a severe bout of diarrhea. The infant rapidly succumbed, and autopsy revealed metastatic foci in the lungs, pleura, esophagus, meninges, pancreas and bone marrow. Osteomyelitis was not described. In a subsequent report of disseminated mucormycosis in a patient with acute granulocytic leukemia, autopsy revealed widespread organ involvement in which bone marrow and blood vessel invasion were apparent, but histologic changes of osteomyelitis were not [22]. The diagnosis of Rhizopus osteomyelitis in our patient was established by roentgenographic, microbiologic and histologic criteria. The presence of tissue invasion by
1676
The American
Journal of Medicine
Volume 66
143
RHIZOPUS OSTEOMYELITIS-ECHOLS
ET AL.
broad, branching, nonseptate hyphae was corroborated by the growth of Rhizopus species from the biopsy material. Blood vessel invasion, considered by some as a requisite for the diagnosis of mucoraceae infection [12], was not observed in the small amount of biopsy material available for microscopic examination. This case of Rhizopus osteomyelitis is unusual in several respects. The source of infection is unknown. The patient had preceding infections of the paranasal sinuses and a pulmonary infection which resolved without establishment of an etiologic agent. Either of these could have been the site from which dissemination occurred. The relapsing and remitting nature of the underlying hematologic disorder may have permitted its coexistence with Rhizopus infection of the respiratory tract without preventing hematogenous spread to the femur. We have assumed that the bone involvement occurred hematogenously, not only because of the absence of any contiguous infection, but also because the bone involved, the femoral metaphysis, is a characteristic site for hematogenous osteomyelitis in this age group [23]. Although both the bursa and the joint space of the right hip were penetrated by needles prior to biopsy, there was no evidence of subsequent infection in either of those sites. The in vitro mitogen studies suggest that the patient had a defect in cell-mediated immunity, although it is not known whether this contributed to, or resulted from, the chronic fungal infection. Stobo et al. [24,25] have described several patients with chronic fungal infections and depressed cellular immunity in whom the depression was mediated by suppressor cells which did not remit when the patient’s clinical conditions improved. In our case, the patient’s response to PHA improved
somewhat after she received a course of amphotericin B therapy, but the response was still less than 50 per cent of control (Table I]. The patient’s lymphocytes did, however, respond in vitro to a saline extract of Rhizopus, whereas the lymphocytes from four control subjects did not. Thus, the patient was apparently able to mount a cell-mediated immune response to the infecting organism, although the magnitude of that response (stimulation index 2-3) was far less than that obtained by incubation of lymphocytes from normal subjects with fungal antigens to which the donors have been previously exposed (stimulation index >20). The low grade immune response may have contributed to the chronicity and local containment of this rare infection. Treatment of mucormycosis osteomyelitis has been largely empiric. In the reported cases of contiguous osteomyelitis, the patients have been managed with surgical debridement and amphotericin B therapy as well as treatment of the underlying disease. This is similar to the experience with other types of mycotic osteomyelitis [3]. Our patient, after receiving more than 1.7 g of amphotericin B, presently has no evidence of progression of the infection. Although surgical curettage may be necessary for complete resolution, technical difficulties resulting from corticosteroid-induced osteopenia and recurrent neutropenia have prevented this treatment modality. ACKNOWLEDGMENT
We gratefully acknowledge the assistance of Carol Dudley, MS., and John Ulrich, Ph.D., of the Microbiology Laboratory of Bernalillo County Medical Center for identification and amphotericin B sensitivities of the Rhizopus organism.
REFERENCES 1. Busey JF: Blastomycosis I. A review of 198 collected cases
from Veterans Administration Hospitals. Am Rev Respir Dis 89: 659, 1964. 2. Iger M: Coccidioidomycosis osteomyelitis. Coccidioidomycosis (Ajello JD), Miami Symposia Specialists, 1977, p 177. 3. Rhangos WC, Chick EW: Mycotic infections of bone. South Med J 57: 664.1964. 4. Simoson MB. Merz WG. Kurlinski IP. et al.: Onoortunistic mycotic osteomyelitis: bone infections due to aspergillus *and candida species. Medicine (Baltimore) 56: 475, 1977. 5. Reddy P, Gorelick DF, Brasher CA, et al.: Progressive disseminated histonlasmosis as seen in adults. Am I Med 48: 629.1970.
January 1979
10.
11.
12. 13.
*
6. Moss SE, McQuown AL: Atlas of Medical Mycology, 3rd ed. Baltimore, Williams & Wilkins Co., 1969, p 167. 7. Gold W, Stout HA, Pagan0 JF. et al.: Amphotericin A and B, antifungal antibiotics produced by a streptomycetes. Antibiotics Annual 1955-1956. New York. Medical EncvcloI pedia, Inc., 1956, p 579. a. Goodwin JS, Messner RP, Bankhurst AD: Suppression of human T-cell mitoaenesis bv orostaelandin: existence of a prostaglandin producing suppressoy cell. J Exp Med 146: 1719.1977.
144
9.
The American Journal of Medicine
14. 15. 16. 17.
Emmons CW, Binford CH, Utz JP, et al.: Medical Mycology, Philadelphia, Lea & Febiger, 1977, p 254. Abramson E, Wilson D, Arky R: Rhinocerebral Phycomycosis in association with diabetes ketoacidosis. Report of two cases and a review of clinical and experimental experience with amphotericin B therapy. Ann Intern Med 66: 735, 1967. Pillsbury HC, Fischer ND: Rhinocerebral mucormycosis. Arch Otolarvnnol 103: 600. 1977. Meyer RD, Arem&ong D: Mucormycosis-changing status. CRC Crit Rev Clin Lab Sci 4: 42.1973. McBride RA, Corson JM, Dammin GJ: Mucormycosis. Two cases of disseminated disease with cultural identification of rhizopus; review of literature. Am J Med 28: 832, 1960. Meyer RD, Rosen P, Armstrong D: Phycomycosis complicating leukemia and lymphoma. Ann Intern Med 77: 871, 1972. Baker RD: The phycomycosis. Ann NY Acad Sci 174: 592, 1970. Medoff G, Kobayashi G: Pulmonary mucormycosis. N Engl J Med 286: 86,1972. Calle S, Klatsky S: Intestinal phycomycosis (Mucormycosis). Am J Chn Path01 45: 264,1966.
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18.
Altschiiler G, Wadleigh J: Cephalic phycomycosis (Rhizopus species). Ariz Med 29: 322,1972. 19. Kaufman RS, Stone G: Osteomyelitis of frontal bone secondary to mucormycosis. NY State J Med 73: 1325,1973. 20. Becker MH, Ngo N, Beranbaum SL: Mycotic infection of the paranasal sinuses. Radiology 96: 49, 1968. 21. Martin FP, Lukeman JM, Ranson RF, et al.: Mucormycosis of the central nervous system associated’with thrombosis of the internal carotid artery. J Pedlatr 44: 437,1954. 22. Meyer RD. Kaplan MH, Ong M. et al.: Cutaneous lesions in
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disseminated mucormycosis. JAMA 225: 737, 1973. 23. Waldvogel FA, Medoff G, Swartz MN: Osteomyelitis. A review of clinical features, therapeutic considerations and unusual aspects. N Engl J Med 282: 198, 1970. 24. Stobo JD, Paul 6, Van Scoy RE. et al.: Suppressor thymusderived lymphocytes in fungal infection. 1Clin Invest 57: 319.1976.
25.
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Stobo JD: Immunosuppression in man: suppression by macrophages can be mediated by interactions with regulatory T-cells. J Immunol 119: 918,1977.
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