Mycobacterial cervical lymphadenitis: the histological features of non-tuberculous mycobacterial infection

Aims: The distinction between nontuberculous mycobacterial (NTM) lymphadeni tis and other causes of cervical lymphadenitis is critical, as different en tities call for different treatments. Despite modern diagnostic techniques for NTM infections their prompt and accurate diagnosis is still difficult. We assessed the value of different histological features in diagnosing clin ically suggestive NTM cervical lymphadenitis in cases of granulomatous cerv ical lymphadenitis. Methods and results: A retrospective study of 30 patients with a clinical d iagnosis of NTM cervical lymphadenitis was carried out. The patients were d ivided into three subgroups and several histological parameters were examin ed in each subgroup. A comparison was made with cases of proven tuberculous lymphadenitis. Four histological features (presence of microabscesses, ill -defined granulomas, noncaseating granulomas and a small number of giant ce lls) were found with significant statistical difference when comparison was made between the NTM group and the tuberculosis group. Conclusions: A rapid and accurate diagnostic procedure for NTM lymphadeniti s is not yet available. Therefore, in the presence of a suggestive clinical picture for NTM lymphadenitis, we propose four histological features which support this diagnosis, thus allowing prompt therapeutic intervention.