Optimal detection and identification of Mycobacterium haemophilum in specimens from pediatric patients with cervical lymphadenopathy

Management of nontuberculous mycobacterial lymphadenitis in a tertiary care children's hospital: A 20year experience

PURPOSE

Nontuberculous mycobacteria are uncommon cause of chronic cervicofacial lymphadenitis in healthy children. We describe clinical features and management strategies of cervicofacial nontuberculous mycobacterium lymphadenitis in a tertiary pediatric hospital.

METHODS

Retrospective analysis of medical records of children discharged from 1992 to 2014 with a diagnosis of cervicofacial nontuberculous mycobacterium was made. Diagnosis certainty was based on microhistological investigations. Clinical stage was evaluated according to lymph node size and presence of fistulas. Successful therapy was defined by the regression of the lymph node enlargement (>75%) or complete surgical excision without relapse.

RESULTS

Cervicofacial nontuberculous mycobacterium was diagnosed in 33 patients. Complete excision was performed in 73% of cases primarily observed in our hospital, while 83% of those referred from other hospitals required further surgical treatment. No case of relapse was observed after one year of follow-up.

CONCLUSIONS

We recommend surgical approach as the first therapeutic option in the management of cervicofacial nontuberculous mycobacterium lymphadenitis.

LEVELS OF EVIDENCE

Prognosis and Retrospective Study - Level II.

Intraventricular granulomatous mass associated with Mycobacterium haemophilum: A rare central nervous system manifestation in a patient with human immunodeficiency virus infection

We report a rare case of Mycobacterium haemophilum presenting as an intraventricular granulomatous mass with loculated hydrocephalus and seizures in a patient with human immunodeficiency virus. M. haemophilum, a slow-growing mycobacteria, causes localized and disseminated disease among immunocompromised hosts. Central nervous system infection with M. haemophilum is extremely rare. Preoperative laboratory testing of our patient for tuberculosis, toxoplasmosis, sarcoidosis and histoplasmosis were negative. Surgical resection of the mass revealed a caseating granuloma that stained positive for acid-fast bacillus suggesting possible tuberculoma. Despite negative testing for tuberculosis, a polymerase chain reaction analysis was ultimately performed from the resected mass which revealed M. haemophilum. To our knowledge, this is the first case of M. haemophilum presenting as an intraventricular mass. We review the clinical manifestations of this pathogen and discuss the medical and surgical 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 as a novel etiology of cervical lymphadenitis in an otherwise healthy adult patient

We describe a case and summarize six additional cases of cervical lymphadenitis in otherwise healthy adults caused by Mycobacterium haemophilum. The organism causes cervicofacial lymphadenitis in healthy children and severe disease in immunocompromised patients but has not been previously reported to cause cervical lymphadenitis in nonimmunocompromised, healthy adults.

Mycobacterium haemophilum and lymphadenitis in immunocompetent children, Israel

The database of a major microbiology laboratory in Israel was searched to determine the prevalence of nontuberculous mycobacterial lymphadenitis in immunocompetent children. We observed a 4-fold increase in nontuberculous mycobacteria isolates during 1985–2006, which was attributable mainly to increased detection of Mycobacterium haemophilum starting in 1996.

Management of nontuberculous mycobacteria-induced cervical lymphadenitis with observation alone

BACKGROUND

Nontuberculous mycobacteria can cause a chronic localized cervicofacial lymphadenitis in immunocompetent children. The recommended treatment is total excision of the affected lymph node. The aim of this study was to describe our experience with an observational approach.

METHODS

Children with chronic nontuberculous mycobacterial (NTM) cervical lymphadenitis, whose parents opted for conservative treatment, were followed at our center from 1990 to 2004. The diagnosis of NTM was based on mycobacterial culture of lymph node specimens obtained by fine needle aspiration. The clinical laboratory and follow-up data were documented.

RESULTS

Ninety-two children with lymph node positive cultures of nontuberculous mycobacterium were included in the study. Mycobacterium avium complex and Mycobacterium hemophilum were isolated in 90% of the cultures. In most cases, the affected lymph nodes underwent violaceous changes with discharge of purulent material for 3-8 weeks. Total resolution was achieved within 6 months in 71% of patients and within 9-12 months in the remainder. At the 2-year follow-up, a skin-colored, flat scar in the region of the drainage was noted. There were no complications.

CONCLUSIONS

We suggest that the observational approach can be effective for managing NTM lymphadenitis in immunocompetent children.

Spinal intradural Mycobacterium haemophilum granuloma in an American Bison (Bison bison)

Mycobacterium haemophilum, a nontuberculous mycobacterium, is a pathogen in immunocompromised human patients. We report a case of M haemophilum-induced granuloma in the spinal cord of an American Bison (Bison bison). M haemophilum infection was diagnosed by sequencing a portion of the 16 S ribosomal DNA and comparing the amplicon sequence with sequences in GenBank.

Mycobacterium haemophilum in an immunosuppressed child

Mycobacterium haemophilum is an emerging cutaneous and systemic pathogen in immunosuppressed adults. Reports in the pediatric literature prior to 2004, limited to immunocompetent children with lymphadenitis, offer a different clinical presentation from that of the immunosuppressed adult. We report an instance of this atypical mycobacterial infection occurring in an immunosuppressed boy with clinical findings similar to those described in immunosuppressed adults.

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.

Emergence of Mycobacterium simiae in respiratory specimens

Temporal changes in epidemiology of non-tuberculous mycobacteria (NTM) infections have hardly been explored. Frequency of isolation of different NTM species varies geographically. We aimed to determine whether the distribution of Mycobacteria species isolated from respiratory specimens had changed from 1996 to 2003. We analysed data on 484 patient mycobacterial isolates from 23,483 respiratory specimens submitted to the Laboratory of Microbiology in a tertiary medical centre. The proportion of patients with Mycobacterium tuberculosis isolates decreased from 44.6% in period I (1996-1999) to 20.6% in period II (2000-2003). Among the NTM, the proportion of some species increased significantly (Mycobacterium simiae: 8.4% to 31.6%; Mycobacterium fortuitum 12% to 20%; and Mycobacterium chelonae 4.8% to 11.3%), while others decreased (Mycobacterium avium complex 31.3% to 17.3%; Mycobacterium kansasii 28.9% to 7.5%; and Mycobacterium haemophilum 1.2% to 0%). These findings disclose major temporal changes in the distribution of mycobacterial species in respiratory specimens with an impressive emergence and takeover of M. simiae.

Direct identification of Mycobacterium haemophilum in skin lesions of immunocompromised patients by PCR-restriction endonuclease analysis

PCR-restriction endonuclease analysis (PRA) was used for direct identification of Mycobacterium haemophilum in clinical specimens from immunocompromised patients. PRA correctly identified M. haemophilum in four smear-positive specimens. Direct identification by PRA takes 2 to 3 working days compared to the 3 to 5 weeks required for culture isolation and identification by conventional methods.

Mycobacteriosis in zebrafish (Danio rerio) research facilities

The Zebrafish International Resource Center was established to support the zebrafish research community, and includes a diagnostic service. One of the most common diseases that we have diagnosed is mycobacteriosis, which represented 18% of the diagnostic cases submitted from November 1999 to June 2003. We describe here the severity of the disease and associated pathological changes of 24 diagnostic cases from 14 laboratories. Identifications of the bacteria are provided for seven of these cases. For two cases in which culture of the organism was not successful, these identifications were based on ribosomal DNA (rDNA) sequence analysis obtained directly from infected tissues. Biochemical characteristics and rDNA sequence analysis from cultures are reported for the other isolates. Two severe outbreaks from different facilities on different continents were associated with an organism identified as Mycobacterium haemophilum based on rDNA sequence from tissues. Another severe outbreak was associated with an organism most closely related to Mycobacterium peregrinum. These species are recognized pathogens of humans, but this is the first report of them from fish. Bacteria identified as Mycobacterium chelonae or M. abscessus were recovered from fish in cases categorized as moderate disease or as an incidental finding. These findings indicate that species of Mycobacterium previously undescribed from fish (i.e., M. haemophilum and M. peregrinum) may pose significant health problems in zebrafish research facilities, whereas species and strains that are already recognized as common in fish usually cause limited disease on a population basis in zebrafish.

First case of Mycobacterium haemophilum infection in an AIDS patient in Italy

Mycobacterium haemophilum, a strongly acid- and alcohol-fast bacillus belonging to the group of non-tuberculous mycobacteria was first described in 1978 as the cause of cutaneous ulcerating lesions in a woman with Hodgkin's disease. Infection due to M. haemophilum is rare but increasing in prevalence in immnunosuppressed subjects, particularly in patients with acquired immunodeficiency syndrome (AIDS) patients. The skin is the most common site of infection with erythematous or violaceous papules and/or nodules that are usually painless at first, but some elements develop into abscesses or ulcers that can become very painful. The incidence of M. haemophilum is unknown, but cases of infection have been reported in Australia, Canada, the United States, France, Israel, the United Kingdom and Taiwan; to date no cases have been reported in Italy, thus the case reported here is apparently the first one observed in our country.

Remission of cutaneous Mycobacterium haemophilum infection as a result of antiretroviral therapy in a Human Immunodeficiency Virus--infected patient

We describe the first Mycobacterium haemophilum infection that occurred in a patient with human immunodeficiency virus in Germany and report 7 newly diagnosed cases of M. haemophilum infection. In the former case, a local M. haemophilum skin infection resolved as a result of successful antiretroviral therapy only; however, that clinical outcome may not be possible for more invasive forms of the disease.

Skin indurations in response to tuberculin testing in patients with nontuberculous mycobacterial lymphadenitis

Mantoux results were examined for 29 children with culture-proven nontuberculous mycobacterial lymphadenitis, and 4 species were isolated: Mycobacterium avium-intracellulare complex (from 14 patients [48%]), Mycobacterium haemophilum (from 12 [41%]), Mycobacterium simiae (from 2 [7%]), and Mycobacterium scrofulaceum (from 1 [3%]); the median indurations for each species were 15.5 mm, 14.5 mm, 20 mm, and 23 mm, respectively, and in 17 cases (59%), they were > or =15 mm. In regions with a low incidence of tuberculosis, lymphadenitis thought to be due to nontuberculous mycobacteria should be managed as such, regardless of Mantoux results, thereby avoiding antituberculosis treatment.

Mycobacterium haemophilum infection in a Japanese patient with AIDS

Mycobacterium haemophilum has been described as a pathogen that causes cutaneous lesions in immunocompromised patients. A specimen from a skin ulcer on the leg of a Japanese patient with acquired immunodeficiency syndrome yielded acid-fast bacilli on blood agar plates after 4 weeks of incubation at 30 degrees C, but the organism was not found on Ogawa egg slants. The organism was identified as M. haemophilum, on the basis of 16S rRNA gene sequence analysis. Prolonged culture in an optimal environment that includes an iron supplement, and growth temperatures at 28 degrees to 33 degrees C are necessary to grow M. haemophilum. Genotypic characterization of 16S rRNA is useful for a rapid diagnosis of this slowly growing mycobacterium.

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.

Histologic reactions to cutaneous infections by Mycobacterium haemophilum

Mycobacterium haemophilum is an emerging pathogen in immunocompromised patients. We report the clinical and histologic findings of 16 skin biopsies from 11 patients with culture-proven infections by M. haemophilum. The patients had leukemia or non-Hodgkin's lymphoma. Ten of them had undergone bone marrow transplantation. When the skin biopsy specimens were taken, a portion of the skin was simultaneously submitted to a microbiology laboratory for cultures. The remaining skin was processed routinely. Acid-fast bacilli were found in 11 of 16 lesions. The number of histologically detectable organisms was typically low: nine biopsies had fewer than three bacilli per 50 oil immersion fields. The most common histologic pattern was a mixed suppurative and granulomatous reaction (7 of 16 biopsies). Four biopsies showed well-formed epithelioid granulomas. Two showed necrosis, one of which was ulcerated. One lesion was a subcutaneous abscess. Two biopsies showed a mixed lichenoid and granulomatous dermatitis. In one of them, the granulomatous reaction was focal and small. One biopsy lacked a granulomatous tissue reaction altogether; it showed an interface dermatitis, a perivascular and periadnexal lymphocytic infiltrate, and necrotizing lymphocytic small vessel vasculitis. A subsequent biopsy from the same patient additionally showed a focal granulomatous reaction. Our observation that infections by M. haemophilum can present with nongranulomatous or pauci-granulomatous reactions without necrosis is of note. Failure to suspect mycobacterial infection in such reactions contributes to probable underreporting of M. haemophilum and to misdiagnoses. Furthermore, our findings emphasize the importance of simultaneous biopsies for culture and histology in immunocompromised patients.

Pulmonary nodule due to Mycobacterium haemophilum in an immunocompetent host

We present a case of a pulmonary nodular lesion in an immunocompetent patient documented at open lung biopsy to be due to Mycobacterium haemophilum. This organism has recently been recognized as a cause of disease in immunocompromised patients, presenting predominantly as skin lesions, arthritis, and rarely pneumonia. Because this mycobacterium is fastidious and difficult to grow without the use of special media and conditions, our case raises the possibility that M. haemophilum could be an underrecognized cause of granulomatous pulmonary lesions and should be considered particularly in cases where smears for acid-fast bacteria are positive but cultures are negative.