M M April1, J M Garelick, G J Nuovo. 1. Department of Surgery, University Hospital and Medical Center, State University of New York at Stony Brook, USA.
Abstract
OBJECTIVE: To determine whether reverse transcriptase (RT) in situ polymerase chain reaction (PCR) can facilitate the diagnosis of nontuberculous ("atypical") mycobacterial (NTM) cervical adenitis. DESIGN: Retrospective review of 12 patients with neck masses clinically diagnosed as NTM cervical adenitis. SETTING: University medical center caring for both ambulatory and hospitalized children. PATIENTS: Twelve pediatric patients (all younger than 9 years) with cervicofacial masses. INTERVENTION: Surgical excision of the presenting mass. MAIN OUTCOME MEASURES: Reverse transcriptase in situ PCR was used to detect mycobacterial RNA in excised tissue. All specimens were also cultured and stained for acid-fast bacilli. RESULTS: Reverse transcriptase in situ PCR was positive for NTM in 7 of 12 cases. CONCLUSIONS: Infection with NTM may be an extremely indolent process, and the success of RT in situ PCR depends on the presence of mycobacterial nucleic acids. Even in cases in which the findings of RT in situ PCR were positive, infected cells were few in number. Because of the sparsity of infection in the positive cases, NTM may be even more rare in the negative cases, ie, those in which mycobacterial nucleic acids do not exist and cannot be detected by any means, including RT in situ PCR. Although RT in situ PCR, cultures, stains for acid-fast bacilli, and tuberculin tests using purified protein derivative are all helpful in diagnosing NTM cervical adenitis, when nucleic acids are present RT in situ PCR is the simplest, most reliable, and quickest to perform and the results are easiest to interpret.
OBJECTIVE: To determine whether reverse transcriptase (RT) in situ polymerase chain reaction (PCR) can facilitate the diagnosis of nontuberculous ("atypical") mycobacterial (NTM) cervical adenitis. DESIGN: Retrospective review of 12 patients with neck masses clinically diagnosed as NTM cervical adenitis. SETTING: University medical center caring for both ambulatory and hospitalized children. PATIENTS: Twelve pediatric patients (all younger than 9 years) with cervicofacial masses. INTERVENTION: Surgical excision of the presenting mass. MAIN OUTCOME MEASURES: Reverse transcriptase in situ PCR was used to detect mycobacterial RNA in excised tissue. All specimens were also cultured and stained for acid-fast bacilli. RESULTS: Reverse transcriptase in situ PCR was positive for NTM in 7 of 12 cases. CONCLUSIONS:Infection with NTM may be an extremely indolent process, and the success of RT in situ PCR depends on the presence of mycobacterial nucleic acids. Even in cases in which the findings of RT in situ PCR were positive, infected cells were few in number. Because of the sparsity of infection in the positive cases, NTM may be even more rare in the negative cases, ie, those in which mycobacterial nucleic acids do not exist and cannot be detected by any means, including RT in situ PCR. Although RT in situ PCR, cultures, stains for acid-fast bacilli, and tuberculin tests using purified protein derivative are all helpful in diagnosing NTM cervical adenitis, when nucleic acids are present RT in situ PCR is the simplest, most reliable, and quickest to perform and the results are easiest to interpret.