Infección por micobacterias no tuberculosas en inmunocompetentes

Ethambutol-resistant Mycobacterium kansasii cervical lymphadenitis in an immunocompetent adult patient: A case report and literature review

Mycobacterium kansasii extrapulmonary infections are infrequent in immunocompetent adults. Rifampin (RIF), clarithromycin (CLR), isoniazid (INH) and ethambutol (EMB) are included in all the standard regimens against M.kansasii. We report a case of a healthy 65-year-old male farmer who presented with isolated right supraclavicular lymphadenopathy. The lymph node FNA showed acid-fast-bacilli and granulomatous inflammation. Quantiferon TB Gold test, HIV serology, and functional immunological studies were all negative or normal. He was put on a standard 4 drugs anti-tuberculous regimen that was switched to RIF + CLR+ INH after the Microbiology lab demonstrated an EMB–resistant Mycobacterium kansasii isotype I strain. The patient was cured after 12 months of therapy. This is the 6th reported case of M. kansasii extrapulmonary lymphadenitis in an immunocompetent adult and the 2nd showing EMB resistance in the world literature. Antimycobacterial regimens against M. kansasii, classically resistant to pyrazinamide (PZA) might also exclude EMB due to its increasing resistance in Europe. A 612 months therapy with at least 2 effective antimycobacterial drugs including RIF + CLR might be enough to treat extrapulmonary M. kansasii infections in immunocompetents.

[Lymphadenitis due to non-tuberculous mycobacteria: Experience over 15 years]

OBJECTIVE

To study the epidemiology, clinical features, diagnosis, therapeutic management, and outcome of non-tuberculous mycobacterial lymphadenitis in a paediatric population of Aragón (Spain).

MATERIAL AND METHODS

A retrospective study was conducted on patients under 15 years-old diagnosed with non-tuberculous mycobacterial lymphadenitis between the years 2000 and 2015.

INCLUSION CRITERIA

patients with lymphadenitis and positive culture. Quantitative values are shown as mean, rank, and standard deviation, and qualitative data as frequencies.

RESULTS

Twenty-seven cases were registered, with a mean age of presentation of 39.9 months (range 10 months-8 years). The mean time between the symptoms onset and first consultation was 1.7±1.1 months. The most frequent location was sub-maxilar in 17/27 cases (63%), on the right side in 59.3%, and size 2.96±1.26cm. Fistulae were observed in 16/27 cases. Tuberculin test was greater than 10mm in 7/24 (29.1%). Microbiological cultures were positive for Mycobacterium avium in 14/27 (51.9%), Mycobacterium intracellulare 3/27 (11.1%), and Mycobacterium lentiflavum 3/27 (11.1%). Combined treatment of antibiotics and surgery was given in 16/27 cases (59.8%), medical treatment only in7/27 (25.9%), and surgical exeresis alone in 4/27 (14.8%). Two patients required a new surgery, and one showed severe neutropenia secondary to rifabutin. Only one case (3.7%) suffered from temporary facial palsy as sequel.

CONCLUSIONS

The most frequent treatment was the combination of antibiotics and surgery. Delay in diagnosis seemed to be responsible for the limited number of exeresis as first option, only one for every seven patients.

Adenitis por micobacterias no tuberculosas

OBJECTIVE

To study the clinical features, epidemiology and outcome of nontuberculous mycobacterial lymphadenitis (NTML).

METHODS

A retrospective study was performed on 54 patients under 14 years old diagnosed with atypical mycobacterial lymphadenitis between 1987 and 2004. Inclusion criteria were: (i) positive polymerase chain reaction (PCR) test or culture; (ii) positive sensitin skin test 6 mm above Mantoux; (iii) histopathologic features compatible with mycobacterial infection and/or positive direct smear for acid-fast bacilli, Mantoux reaction less than 15 mm, a normal chest radiograph, absence of exposure to an adult with tuberculosis, negative Mantoux test reactions in family members, and exclusion of other causes of granulomatous adenitis.

RESULTS

Fifty-four patients were included in the study. The number of NTML cases increased notably from 1996, coinciding with a decrease in cases of tuberculous adenitis. The mean age was 35 months (range: 14 months-6 years). Submandibular nodes were involved in 22 of 63 cases of adenitis (34.9%) and cervical nodes were involved in 21 (33.3%). In 8/42 patients (19%) the tuberculin skin test was larger than 10 mm. Cultures were positive in 52.9% of the cases (18/34) and PCR in 53.3% (8/15). The most frequently isolated mycobacteria was Mycobacterium avium (61%). Therapy failed in 8/21 patients receiving antibiotics (38%), in 10/13 patients with drainage alone (77%) and in none of the patients who underwent surgery (8/8).

CONCLUSIONS

Nontuberculous mycobacterial adenitis has become more frequent in our hospital since 1996. Cultures do not always allow isolation of mycobacteria and the Mantoux test frequently yields false positive results, thus hampering diagnosis. The most effective treatment was surgical excision. Nevertheless, when the surgical approach is difficult or there is postoperative recurrence, pharmacological treatment can be useful.

[Pediatric infections caused by nontuberculous mycobacteria]

During the last few years, nontuberculous mycobacteria (NTM) have been isolated with increasing frequency in our environment. However, there are only a few reports of pediatric NTM infections in Spain (13 articles since 1990). This article presents an update of the epidemiology, diagnostic methods, and treatment of these infections in children. The most frequent clinical syndromes caused by NTM include lymphadenitis, pulmonary and disseminated infections in immunocompromised children. NTM cervical adenitis usually causes chronic infection associated with sinus tract formation and scarring. The treatment of choice is surgical excision of the involved node. Incision and drainage of the enlarged node should be avoided because it can lead to chronic drainage or sinus tract formation. Medical treatment with azithromycin or clarithromycin associated with rifabutin, ethambutol or ciprofloxacin should be reserved for cases in which the family refuses surgery, a recurrence occurs or complete excision is impossible. Pulmonary disease caused by NTM is relatively rare in immunocompetent children, but is increasingly reported in children with cystic fibrosis. In these patients, the clinical significance of the presence of NTM in the sputum is unclear. The persistence of positive cultures, especially if bacilloscopy is positive and the patient shows clinical evidence of pulmonary disease exacerbation, is an indication to start treatment. Disseminated infection caused by NTM can appear in patients with severe immunodepression, especially in HIV-infected children with CD4 cell counts of less than 100 cells/mm3. Early antibiotic therapy with at least three drugs including a macrolide, and immune recovery with aggressive antiretroviral therapy are the keys to improving quality of life and survival in these patients.

[Usefulness of chemotherapy associated with surgery in the management of nontuberculous mycobacterial adenitis]

BACKGROUND

In recent years, lymphadenitis caused by atypical mycobacteria (also called nontuberculous mycobacteria [NTMB] or, more recently, environmental) have played a significant role in the differential diagnosis of adenitis in non-immunocompromised children.

OBJECTIVES

To describe the clinical and pathological findings in childhood NTMB adenitis and study the possible usefulness of antimicrobial therapy in addition to surgery.

METHODS

We present eight cases of neck lymphadenitis occurring over a 5-year period. All of the children received combined chemotherapy, and six also underwent surgery. Of the two remaining patients, the parents of one child refused surgery and a watchful approach was adopted in the other.

RESULTS

Complete clinical recovery was achieved in all patients except one who did not undergo surgery.

CONCLUSIONS

Prolonged administration of two antibiotics (of which one must be clarithromycin) in addition to surgery was well-tolerated and could be useful in patients with NTMB neck lymphadenitis.