Abstract
Introduction: Investigations of tuberculous lymphadenitis are challenging for clinicians. Using multimodality patterns may yield a better outcome. The objective is to compare the various laboratory methods; GeneXpert, culture, ZN stain and Auramine-Rhodamine stain in diagnosing tuberculous lymphadenitis. Method: This study is a prospective cross-sectional laboratory-based study. The study was conducted in Khartoum, Sudan. Specimens obtained from lymph nodes were examined cytologically, culture, GeneXpert, Auramine-Rhodamine stain and ZN stain laboratory methods were applied for all specimens, and all cases were initially diagnosed as tuberculous lymphadenitis by FNAC. Patients' sociodemographic data anthropometric measurements, clinical examination and diagnostic tools were also gathered. SPSS version 23 was used for data analysis.
Results: a total number of 105 cases were included, 53.3% were males. The mean age was 27.29 ± 15.94. The most affected age group was 19 – 30 (33.3%). The most affected lymph node group was the cervical group 83 (79.0%); furthermore, 81(77.1%) patients had a single lymph node affected while 24(22.9%) cases had multiple lymph nodes. The main cytomorphological pattern identified was necrotizing granulomatous lymphadenitis 79(75.2%). GeneXpert Positive cases were (41.0%), ZN staining (4.8%), Auramine- rhodamine stain (5.7%) and culture showed growth among (45.7%) of the cases. Sensitivity against FNAC was as follow: culture 64.81%, GeneXpert 62.87%, ZN stain 51.22% and Auramine-Rhodamine stain 51.47%. On the other hand, sensitivity and specificity against culture was calculated as follow: FNAC 100%, GeneXpert 80.0%, ZN stain 51.61% and Auramine-Rhodamine stain 53.33%. Specificity, as based on culture, was as follows FNAC 54.28%, GeneXpert 89.06%, ZN stain 96.61% and Auramine-Rhodamine stain 100%.
Conclusion: combining various diagnostic methods for caseating necrotizing cytomorphology cases yields less than 50% positivity. FNAC is recommended as the first-line test for suspected tuberculous lymphadenitis due to its higher sensitivity, rapidity, practicality, and cost-effectiveness. In inconclusive cases or those with a suppurative background, especially suspected TBLN, culture and GeneXpert are advised.