[Nontuberculous mycobacteria in cervical lymphadenopathies of HIV positive and HIV-negative adults]

Rev Med Inst Mex Seguro Soc. 2019 Jan 28;56(5):456-461.
[Article in Spanish]

Abstract

Background: Tuberculosis is a global public health problem, especially in emerging countries. Mycobacterium tuberculosis is the main cause of cervical lymphadenopathy; nontuberculous mycobacteria are relatively common in children and rare in adults.

Objective: To identify and establish the frequency of infectious etiology by nontuberculous mycobacteria in Mexican adult patients with cervical lymphadenopathy.

Methods: The study included 85 patients over 18 years with cervical lymphadenopathy; 45 were HIV-positive, 40 were HIV-negative; they had no history of tuberculosis treatment and were selected from a third-level hospital. It was carried out a biopsy of the lymph node for the histopathological study, a search for acid-fast bacilli, a tube culture to indicate growth of Mycobacterium BACTEC (MGIT-960) and identification of mycobacterial strain by PCR-RFLP (restriction fragment length polymorfism) of hsp65.

Results: In 42 HIV-positive patients (93%), strains corresponded to Mycobacterium tuberculosis complex, two (4.4%) to M. intracellulare and one (2.2%) to M. gordonae. Among HIV-negative patients, 39 of strains (97.5%) corresponded to patients with M. tuberculosis complex and one strain (2.5%) to M. fortuitum.

Conclusion: The presence of nontuberculous mycobacteria was found in 4.7% of all cases. Despite this low frequency, it must be taken into account as a possible cause of lymphadenopathy, since its prompt identification enables introducing specific treatment.

Introducción: la tuberculosis es un problema de salud pública mundial, sobre todo en países emergentes. El Mycobacterium tuberculosis es el principal causante de las adenopatías cervicales; las micobacterias no tuberculosas son relativamente frecuentes en el niño y raras en adultos.

Objetivo: identificar y establecer la frecuencia de la etiología infecciosa por micobacterias no tuberculosas (MNT) en pacientes adultos mexicanos con linfadenopatias cervicales.

Métodos: se estudiaron 85 pacientes mayores de 18 años, con linfadenopatía cervical, 45 con positividad al virus de la inmunodeficiencia humana (VIH) y 40 VIH negativos, sin antecedentes de tratamiento antituberculoso, seleccionados en un hospital de concentración de especialidad de tercer nivel. Se realizó biopsia de nodo linfático para su estudio histopatológico, búsqueda de bacilos ácido-alcohol resistentes, cultivo en el tubo indicador del crecimiento de Mycobacterium BACTEC (MGIT-960) y la identificación de cepa micobacteriana por PCR-RFLP (restriction fragment lenght polymorfism) de hsp65.

Resultados: las cepas correspondieron al complejo Mycobacterium tuberculosis en 42 pacientes VIH positivos (93%), dos (4.4%) a M. intracellulare y una (2.2%) a M. gordonae. Las cepas correspondieron al complejo M. tuberculosis en 39 pacientes VIH negativos (97.5%) y una a M. fortuitum (2.5%).

Conclusión: la presencia de MNT se encontró en 4.7% de todos los casos. A pesar de su baja frecuencia, deben ser tomadas en cuenta como posible causa de linfadenopatías, porque su identificación oportuna permite instaurar un tratamiento específico.

Keywords: Tuberculosis, Lymph Node; Mycobacterium tuberculosis; Nontuberculous Mycobacteria; Cervical Lymphadenopathy.

Publication types

  • English Abstract

MeSH terms

  • AIDS-Related Opportunistic Infections / diagnosis
  • AIDS-Related Opportunistic Infections / epidemiology*
  • Adolescent
  • Adult
  • Aged
  • Case-Control Studies
  • Female
  • Follow-Up Studies
  • Humans
  • Lymphadenopathy / diagnosis
  • Lymphadenopathy / epidemiology*
  • Lymphadenopathy / virology
  • Male
  • Mexico / epidemiology
  • Middle Aged
  • Mycobacterium Infections, Nontuberculous / diagnosis
  • Mycobacterium Infections, Nontuberculous / epidemiology*
  • Mycobacterium Infections, Nontuberculous / virology
  • Prospective Studies
  • Tuberculosis, Lymph Node / diagnosis
  • Tuberculosis, Lymph Node / epidemiology*
  • Tuberculosis, Lymph Node / virology
  • Young Adult