Two cases of Mycobacterium haemophilum infection in a renal-dialysis unit

Management of infections due to nontuberculous mycobacteria in solid organ transplant recipients-Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

These updated guidelines from the American Society of Transplantation Infectious Diseases Community of Practice review the epidemiology, diagnosis, prevention, and management of nontuberculous mycobacterial infections in the pre- and post-transplant period. NTM commonly cause one of five different clinical syndromes: pleuropulmonary disease, skin and soft tissue infection, osteoarticular infection, disseminated disease, including that caused by catheter-associated infection, and lymphadenitis. Diagnosis of these infections can be challenging, particularly when they are isolated from nonsterile spaces, owing to their ubiquity in nature. Consequently, diagnosis of pulmonary infections with these pathogens requires fulfillment of microbiologic, radiographic, and clinical criteria to address this concern. A combination of culture and molecular diagnostic techniques is often required to make a species-level identification. Treatment varies depending on the species isolated and is complex, owing to drug toxicities, need for long-term multidrug regimens, and consideration of complex drug-drug interactions between antimicrobials and immunosuppressive agents. Given these treatment challenges, efforts should be made in both the hospital and community settings to limit exposure to these pathogens to the extent feasible.

Non-tuberculous mycobacterial infections in solid organ transplant recipients: An update

Non-tuberculous mycobacteria are ubiquitous environmental organisms that are now increasingly recognized as important causes of clinical disease in solid organ transplant recipients. Risk factors of non-tuberculous mycobacteria infection are severe immunologic defects and structural abnormalities. Lung transplant recipients are at higher risk for non-tuberculous mycobacterial disease compared to recipients of other solid organs. The clinical presentation could be skin and soft tissue infection, osteoarticular disease, pleuropulmonary infection, bloodstream (including catheter-associated) infection, lymphadenitis, and disseminated or multi-organ disease. Management of non-tuberculous mycobacteria infection is complex due to the prolonged treatment course with multi-drug regimens that are anticipated to interact with immunosuppressive medications. This review article provides an update on infections due to non-tuberculous mycobacteria after solid organ transplantation, and discusses the epidemiology, risk factors, clinical presentation, and management.

Clinical manifestations, diagnosis, and treatment of Mycobacterium haemophilum infections

Mycobacterium haemophilum is a slowly growing acid-fast bacillus (AFB) belonging to the group of nontuberculous mycobacteria (NTM) frequently found in environmental habitats, which can colonize and occasionally infect humans and animals. Several findings suggest that water reservoirs are a likely source of M. haemophilum infections. M. haemophilum causes mainly ulcerating skin infections and arthritis in persons who are severely immunocompromised. Disseminated and pulmonary infections occasionally occur. The second at-risk group is otherwise healthy children, who typically develop cervical and perihilar lymphadenitis. A full diagnostic regimen for the optimal detection of M. haemophilum includes acid-fast staining, culturing at two temperatures with iron-supplemented media, and molecular detection. The most preferable molecular assay is a real-time PCR targeting an M. haemophilum-specific internal transcribed spacer (ITS), but another approach is the application of a generic PCR for a mycobacterium-specific fragment with subsequent sequencing to identify M. haemophilum. No standard treatment guidelines are available, but published literature agrees that immunocompromised patients should be treated with multiple antibiotics, tailored to the disease presentation and underlying degree of immune suppression. The outcome of M. haemophilum cervicofacial lymphadenitis in immunocompetent patients favors surgical intervention rather than antibiotic treatment.

Atypical focal osteomyelitis as initial manifestation of AIDS

Persistent pain development after a skeletal contusion rarely poses the diagnosis of osteomyelitis. We report the case of a fibular head contusion as an initial manifestation of a focal abscess development in a healthy young patient. The traditional treatment of surgical drainage revealed the presence of an atypical Mycobacterium haemophilum isolates in the abscess. This lead to further investigations that concluded and established the diagnosis of AIDS. Conclusion. Isolation of an atypical Mycobacterium haemophilum in any abscess should lead the physician to accomplish further investigations and look for AIDS even in young healthy subjects.

Mycobacterium haemophilum and Histoplasma capsulatum coinfection in a renal transplant patient

We report the case of a 22-year-old man who presented with a Mycobacterium haemophilum and Histoplasma capsulatum coinfection occurring 21 years after a living-donor-related renal transplant.

Mycobacterium haemophilum osteomyelitis: case report and review of the literature

Background

Mycobacterium haemophilum is a slow-growing, fastidious, iron-requiring microorganism that, relative to other non-tuberculous mycobacterial species, has rarely been documented as a cause of human infection. This microorganism appears to be acquired via environmental exposure although its natural habitat and mode of acquisition are unknown. It has primarily been implicated as a cause of ulcerating cutaneous or subcutaneous nodular skin lesions, particularly in immunocompromised patients, although infections at extracutaneous sites have also been described. Osteomyelitis, while rarely documented, appears to be an important complication of infection with M. haemophilum in these patients.

Case presentation

We describe a unique case of culture-confirmed M. haemophilum osteomyelitis in an adult woman with polycythemia vera and review the world literature on bone infections due to this organism.

Conclusion

Mycobacterium haemophilum is an important but infrequently encountered cause of osteomyelitis in immunocompromised patients, often requiring months to years of medical therapy, with or without surgery, to effect a clinical cure.

Nontuberculous mycobacterial infection in hematopoietic stem cell and solid organ transplant recipients

Nontuberculous mycobacteria (NTM) are ubiquitous environmental organisms. In immunocompetent hosts, they are a rare cause of disease. In immunocompromised hosts, disease due to NTM is well documented. Reports of NTM disease have increased in hematopoietic stem cell transplant (HSCT) and solid organ transplant (SOT) recipients. This increase may reflect increased numbers of transplants, intensification of immune suppressive regimens, prolonged survival of transplant recipients, and/or improved diagnostic techniques. The difficulty of diagnosis and the impact associated with infections due to NTM in HSCT and SOT recipients necessitates that, to ensure prompt diagnosis and early initiation of therapy, a high level of suspicion for NTM disease be maintained. The most common manifestations of NTM infection in SOT recipients include cutaneous and pleuropulmonary disease, and, in HSCT recipients, catheter-related infection. Skin and pulmonary lesions should be biopsied for histologic examination, special staining, and microbiologic cultures, including cultures for bacteria, Nocardia species, fungi, and mycobacteria. Mycobacterial infections associated with catheters may be documented by tunnel or blood (isolator) cultures. Susceptibility testing of mycobacterial isolates is an essential component of optimal care. The frequent isolation of NTM other than Mycobacterium avium complex (MAC) from transplant recipients limits the extrapolation of therapeutic data from human immunodeficiency virus-infected individuals to the population of transplant recipients. Issues involved in the management of NTM disease in transplant recipients are characterized by a case of disseminated infection due to Mycobacterium avium complex in a lung transplant recipient, with a review of the relevant literature.

Mycobacterium haemophilum in immunocompromised patients

Mycobacterium haemophilum, a recently described pathogen, can cause an array of symptoms in immunocompromised patients. To date, 90 patients with this infection have been described worldwide. We report our institution's experience with 23 patients who were treated from 1990 through 2000. Fourteen patients had undergone bone marrow transplantation, 5 were infected with human immunodeficiency virus, 3 had hematologic malignancies, and 1 had no known underlying immunosuppression. Clinical syndromes on presentation included skin lesions alone in 13 patients, arthritis or osteomyelitis in 4 patients, and lung disease in 6 patients. Although patients with skin or joint involvement had favorable outcomes, 5 of 7 patients with lung infection died. Prolonged courses of multidrug therapy are required for treatment. A diagnosis of M. haemophilum infection must be considered for any immunocompromised patient for whom acid-fast bacilli are identified in a cutaneous, synovial fluid or respiratory sample or for whom granulomas are identified in any pathological specimen.

Rapid identification of cutaneous infections by nontubercular mycobacteria by polymerase chain reaction-restriction analysis length polymorphism of the hsp65 gene

BACKGROUND

Nontubercular mycobacteria (NTM) may cause cutaneous infections which are difficult to interpret due to the variability of the clinical manifestations. This study involved eight patients (four men and four women) with primary cutaneous infections caused by NTM; the skin lesions included dermo-hypodermal abscesses, suppurative granulomas, and papulonodules localized on the legs, arms, hands, and face. The general condition of the patients was relatively good and they were not immunosuppressed.

METHODS

All samples were processed with standard methods and the isolates were identified by pattern restriction analysis after polymerase chain reaction (PCR-PCA) amplification of the heat shock protein of 65 kDa.

RESULTS

In this way, we were able to identify three Mycobacterium chelonae strains, two Mycobacterium marinum, two Mycobacterium fortuitum, and one Mycobacterium avium. The lesions disappeared in 3 or 4 weeks after treatment with two or more antimicrobials.

CONCLUSIONS

For a correct diagnosis of cutaneous infection by NTM, demonstrating the presence of mycobacteria is essential; routinely available techniques lack sensitivity and are extremely tedious; often mycobacteria are not seen after acid-fast stain. We used PCR-PCA to identify mycobacteria grown in liquid media; the time of identification of mycobacteria was shortened relative to conventional methods.

An annular plaque due to Mycobacterium haemophilum infection in a patient with AIDS

Infections with mycobacteria are of importance in the differential diagnosis of skin lesions in immunocompromised patients. We report the case of a human immunodeficency virus (HIV)-infected patient who presented with an annular plaque as cutaneous manifestation of Mycobacterium haemophilum. Improvement of the immunologic status is important for successful treatment. Complete resolution was only observed when the antimycobacterial therapy was combined with antiretroviral therapy.

The spectrum of mycobacterial infection after lung transplantation

Despite the success of lung transplantation, infection is one of the leading causes of morbidity and mortality. Mycobacterial infections have been reported rarely, with the majority due to Mycobacterium tuberculosis. Our aim was to assess the incidence, etiology, and clinical outcome of mycobacterial infection after lung transplantation; to do so, we have studied retrospectively all lung and heart- lung transplants performed over a 12-yr period between November 1986 and June 1998 (n = 261). Twenty-three patients (9%) (M:F, 11:12) were diagnosed with mycobacterial infections in 25 sites, including n = 19, pulmonary (M. avium complex [n = 13], M. tuberculosis [n = 2], M. abscessus [n = 2], M. asiaticum [n = 1], and M. kansasii [n = 1]) and n = 6 extrapulmonary (M. haemophilum [n = 5] and M. abscessus [n = 1]) infections. Time to diagnosis from transplantation was 677 +/- 735 d (range, 2- 3,086 d). Three episodes of transient colonization with M. avium were not treated; the remaining (22 of 25, 88%) were treated. Initial baseline therapy for nontuberculous mycobacteria included clarithromycin, rifampicin, ciprofloxacin, and/or ethambutol. All cutaneous lesions resolved completely, while clinical and graft function improved in 11 of 16 (69%) and 8 of 16 (50%) of patients treated, respectively. Seventeen of 23 patients (72%) survived at a follow-up of 1,658 +/- 759 d (range, 522-3,285 d). Complications, predominantly due to rifampicin, included gastrointestinal intolerance and an increased tendency for rejection. There were no deaths attributable to mycobacterial disease or therapy. We conclude that mycobacterial infection, particularly due to nontuberculous mycobacteria, is relatively common after lung transplantation and may be an unrecognized cause of graft dysfunction. Early treatment of cutaneous lesions is associated with excellent control; however, graft dysfunction may be permanent. Although drug toxicity and interactions with immunosuppressive agents were not infrequent, the majority of these infections can be managed successfully.

Emergence of a unique group of necrotizing mycobacterial diseases

Although most diseases due to pathogenic mycobacteria are caused by Mycobacterium tuberculosis, several other mycobacterial diseases-caused by M. ulcerans (Buruli ulcer), M. marinum, and M. haemophilum-have begun to emerge. We review the emergence of diseases caused by these three pathogens in the United States and around the world in the last decade. We examine the pathophysiologic similarities of the diseases (all three cause necrotizing skin lesions) and common reservoirs of infection (stagnant or slow-flowing water). Examination of the histologic and pathogenic characteristics of these mycobacteria suggests differences in the modes of transmission and pathogenesis, though no singular mechanism for either characteristic has been definitively described for any of these mycobacteria.

Infections in solid-organ transplant recipients

Solid-organ transplantation is a therapeutic option for many human diseases. Infections are a major complication of solid-organ transplantation. All candidates should undergo a thorough infectious-disease screening prior to transplantation. There are three time frames, influenced by surgical factors, the level of immunosuppression, and environmental exposures, during which infections of specific types most frequently occur posttransplantation. Most infections during the first month are related to surgical complications. Opportunistic infections typically occur from the second to the sixth month. During the late posttransplant period (beyond 6 months), transplantation recipients suffer from the same infections seen in the general community. Opportunistic bacterial infections seen in transplant recipients include those caused by Legionella spp., Nocardia spp., Salmonella spp., and Listeria monocytogenes. Cytomegalovirus is the most common cause of viral infections. Herpes simplex virus, varicella-zoster virus, Epstein-Barr virus and others are also significant pathogens. Fungal infections, caused by both yeasts and mycelial fungi, are associated with the highest mortality rates. Mycobacterial, pneumocystis, and parasitic diseases may also occur.

Mycobacterium haemophilum: microbiology and expanding clinical and geographic spectra of disease in humans

Reports of the association of Mycobacterium haemophilum with disease in humans have greatly increased. At least 64 cases have now been reported, with symptoms ranging from focal lesions to widespread, systemic disease. The organism is now known to cause primarily cutaneous and subcutaneous infection, septic arthritis, osteomyelitis, and pneumonitis in patients who are immunologically compromised and lymphadenitis in apparently immunocompetent children. Underlying conditions in the compromised patients have included AIDS; renal, bone marrow, and cardiac transplantation; lymphoma; rheumatoid arthritis; marrow hypoplasia; and Crohn's disease. Reports have originated from diverse geographic areas worldwide. The epidemiology of M. haemophilum remains poorly defined; there appears to be a genetic diversity between strains isolated from different regions. The organism is probably present in the environment, but recovery by sampling has not been successful. M. haemophilum has several unique traits, including predilection for lower temperatures (30 to 32 degrees C) and requirement for iron supplementation (ferric ammonium citrate or hemin). These may in the past have compromised recovery in the laboratory. Therapy has not been well elucidated, and the outcome appears to be influenced by the patient's underlying immunosuppression. The organisms are most susceptible to ciprofloxacin, clarithromycin, rifabutin, and rifampin. Timely diagnosis and therapy require communication between clinician and the laboratory.

Nontuberculous mycobacterial infections

OBJECTIVE

To review the epidemiology, clinical manifestations, diagnosis, and treatment of nontuberculous mycobacterial infections other than Mycobacterium avium complex (MAC).

DATA SOURCES

A MEDLINE search of English-language literature pertaining to nontuberculous mycobacteria other than MAC was performed. Additional literature was obtained from reference lists of pertinent articles identified through the search.

STUDY SELECTION AND DATA EXTRACTION

All articles were considered for possible inclusion in the review. Information judged by the author to be pertinent was selected for discussion.

DATA SYNTHESIS

Mycobacterial infections, including those caused by nontuberculous mycobacteria other than MAC, have assumed greater importance over the past decade, due in part to the changing spectrum of immunosuppression as manifested by organ transplantation and HIV infection. Many pathogenic nontuberculous mycobacteria have been identified that are associated with a wide variety of localized, organ-specific, and systemic infections. Of concern, these organisms exhibit variable, species-specific susceptibility to traditional antimycobacterial drugs and other antimicrobials. In addition, long treatment courses and adjunctive surgical therapy are often required to effect cure. Important antimicrobials for the management of these infections include cefoxitin, imipenem/cilastatin, aminoglycosides (other than streptomycin), tetracyclines, macrolides, and trimethoprim/sulfamethoxazole, as well as traditional antimycobacterials.

CONCLUSIONS

Nontuberculous mycobacteria have assumed an increasing role in disease etiology in both nonimmunocompromised and immunocompromised individuals. Advent of rapid diagnostic techniques and susceptibility testing has allowed the clinician to identify these organisms and initiate effective treatment on a more timely basis with an improved chance for cure. Few therapeutic agents are available for treatment of these infections, many of which are not considered classic antimycobacterials.

Mycobacterium haemophilum: an emerging pathogen

Mycobacterium haemophilum is emerging as a pathogen of immunocompromised patients particularly those with AIDS and organ transplants. Infection has also occurred in healthy children. Adults usually present with cutaneous manifestations, septic arthritis or occasionally pneumonia. Children have perihilar, cervical or submandibular adenitis. The organism grows on mycobacterial media supplemented with ferric ammonium citrate or hemin, incubated at 30 degrees C to 32 degrees C, two to three weeks after inoculation. The most active antimicrobial agents in vitro are amikacin, ciprofloxacin, clarithromycin, rifabutin and rifampin. Development of resistance to the rifamycins has been demonstrated after patients were treated for several months with several antimycobacterial agents, including the rifamycins. Treatment for several months with at least two agents demonstrated to have low MICs for the organism has been shown to be effective.

DNA polymorphisms detected in Mycobacterium haemophilum by pulsed-field gel electrophoresis

Nineteen isolates of Mycobacterium haemophilum were analyzed by pulsed-field gel electrophoresis of large restriction fragments generated by digestion of chromosomal DNA with XbaI. Six patterns were observed. Twelve of 16 M. haemophilum isolates (75%) collected in the New York Metropolitan Area from 1990 to 1991 shared the same pattern, including all six isolates submitted from one hospital. Two different patterns were seen among the other four isolates. Individual isolates from Albany, N.Y., Florida, and Texas had unique patterns. Pulsed-field gel electrophoresis is the first method reported with the capability to type strains of M. haemophilum and will hopefully provide insight into the source and transmission of this emerging pathogen.

Activities of antimicrobial agents against clinical isolates of Mycobacterium haemophilum

Mycobacterium haemophilum, first described in 1978, can cause severe infections of skin, respiratory tract, bone, and other organs of immunocompromised patients. There is no standardized antimicrobial susceptibility test, and for the 27 reported cases, a variety of test methods have been used. This paper reports the in vitro test results for 17 isolates of M. haemophilum recovered from 12 patients in the New York City area. MICs of 16 antimicrobial agents were determined in microtiter trays containing Middlebrook 7H9 broth plus 60 microM hemin, inoculated with 10(6) CFU of the organism per ml and incubated at 30 degrees C for 10 days. Ethambutol, ethionamide, tetracycline, cefoxitin, and trimethoprim-sulfamethoxazole were inactive against initial isolates from the 12 patients. Isoniazid was weakly active with a MIC for 50% of strains tested (MIC50) of 8 micrograms/ml and a MIC90 of > 32 micrograms/ml. Three quinolones, ciprofloxacin, ofloxacin, and sparfloxacin, were moderately active with MIC50s of 2 to 4 micrograms/ml and MIC90s of 4 to 8 micrograms/ml. Amikacin and clofazamine were active with MIC90s of 4 and 2 micrograms/ml, respectively. Clarithromycin was the most active macrolide with a MIC90 of < or = 0.25 microgram/ml. The MIC90 of azithromycin was 8 micrograms/ml, and the MIC90 of erythromycin was 4 micrograms/ml. The rifamycins were active with a MIC90 of 1 microgram/ml for rifampin and one of < or = 0.03 micrograms/ml for rifabutin. For a second isolate from the skin of one patient and a isolate from an autopsy culture of the spleen of a second patient, MICs of rifampin and rifabutin were > 16 microgram/ml, whereas initial isolates were inactivated by low concentrations of the rifamycins. Both patients had been treated for several months with several antimicrobial agents, including a rifamycin.

Osteomyelitis due to Mycobacterium haemophilum in a patient with AIDS

A case of osteomyelitis resulting from infection with Mycobacterium haemophilum in a patient with the Acquired Immunodeficiency Syndrome (AIDS) and Hodgkin's disease is described. The clinical features and response to therapy are examined and compared to previous reported cases. Mycobacterium haemophilum infection in immunocompromised patients usually results in cutaneous lesions but osteomyelitis may be the presenting feature. Tissue samples should be obtained early for microbiological examination and treatment should consist of surgical debridement and appropriate antimicrobial therapy.

A cluster of four cases of Mycobacterium haemophilum infection

Four cases of infection with Mycobacterium haemophilum occurred at a single hospital in a seven-month period. Only 22 cases have been reported since 1976. All four patients were immunocompromised; two had AIDS and two were the first known recipients of allogeneic bone marrow transplants (BMT) to develop the infection. One BMT recipient died of Mycobacterium haemophilum pneumonia. The organism requires hemin or ferric ammonium citrate and incubation of media at 30 degrees C for optimum growth. Clinicians and microbiologists should consider infection with Mycobacterium haemophilum, particularly when specimens are from immunocompromised patients with unexplained illness and/or when acid-fast bacilli are seen on smear.

Mycobacterium haemophilum causing perihilar or cervical lymphadenitis in healthy children

We describe five apparently immunologically normal children with infection caused by Mycobacterium haemophilum and resulting in perihilar or cervical lymphadenitis. Clinical distinction from Mycobacterium tuberculosis infection could be made by culture only, because differential Mantoux test results suggested tuberculosis. Treatment of these children involved chemotherapy or surgery or both, and outcome in all cases has been excellent. We believe that M. haemophilum should be added to the list of non-tuberculosis mycobacteria known to cause lymphadenitis in otherwise healthy children.

Two cases of Mycobacterium haemophilum infection in Canada

In 1987, Mycobacterium haemophilum was isolated from cutaneous lesions, a lymph node, and the right eye of a male patient with acquired immunodeficiency syndrome and also from a cervical lymph node in a 3-year-old girl. These two cases are the first M. haemophilum infections to be reported in Canada.