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Objectives:The objectives were to correlate the modified fluorescent method with the conventional Ziehl–Neelsen (ZN) method for the detection of acid-fast bacilli (AFB) and, also to study the efficacy and advantages of using the auramine–rhodamine stain on lymph node aspirates under fluorescent microscopy.Methods:In 108 consecutive patients with a clinical suspicion of tuberculosis (TB) presenting with lymphadenopathy, fine needle aspirations were performed. Smears from the aspirates were processed for routine cytology, the conventional ZN method, and the modified fluorescent method. The significance of the modified fluorescent method over the conventional ZN method was analyzed using the chi-square test.Results:Out of 108 aspirates, 102 were studied and remaining 6 were excluded from the study due to diagnosis of malignancy in 4.04% (4/6) and inadequate aspiration in 2.02% (2/6). Among the 102 aspirates, 44.11% (45/102) were positive for AFB on the conventional ZN method, 58.9% (60/102) were indicative of TB on cytology, while the smear positive increased to 81.37% (83/102) on the modified fluorescent method.Conclusions:Fluorescent microscopy has the advantage of speed and ease of screening, and reduces observer fatigue. The modified fluorescent method was found to be more advantageous than routine cytology and conventional ZN method, particularly in paucibacillary cases. The bacillary positivity rates were higher in the modified fluorescent method than in the ZN method. Hence, the modified fluorescent method can be an adjuvant when used with routine cytology for the identification of AFB.

Both 'unstained' and 'de stained' sections can be used for rapid screening of sclerotic bodies. 'De stained' sections can be used as a suitable substitute for special stains for confirmation and for retrospective review of all verrucous lesions to diagnose the missed lesion. Clinical suspicion is very important in the diagnosis of chromoblastomycosis as it helps pathologist to screen for diagnostic sclerotic bodies.

Fine-needle aspiration (FNA) cytology of the thyroid is usually performed on an outpatient basis. The results of FNA are operator dependent and may be affected by the lesion characteristics and the aspiration technique. In current practice ultrasound (US) is widely used to guide the needle for aspiration of nondominant nodules. Our study aimed to compare the free-hand FNA with US-guided FNA in the evaluation of thyroid nodules. A total of 91 cases of thyroid lesions were studied at the Department of Pathology, Karnataka Institute of Medical Sciences, Hubli, India. All the cases underwent free-hand and US-guided FNA. The cytological samples from both procedures were analyzed for adequacy, cytological features, and possible diagnosis. The results were correlated with histopathological diagnosis whenever possible. Of 91 aspirates, 89 were satisfactory and 2 were unsatisfactory on US-guided FNA, whereas 85 were satisfactory and 6 were unsatisfactory in free-hand FNA. Of 91 cases 68 (74.7%) were nonneoplastic lesions and 21 (23.1%) were neoplastic lesions in US-guided FNA, whereas 67 cases (73.6%) were nonneoplastic and 18 cases (19.8%) were neoplastic in free-hand FNA. Histopathological study was possible in 25 patients, among whom 15 lesions were nonneoplastic and 10 were neoplastic. Sensitivity and specificity of US-guided FNA to detect neoplastic lesions were 81.81% and 92.85%, respectively, compared with free-hand FNA, for which the sensitivity and specificity were 54.54% and 92.85%, respectively. The diagnostic accuracy of guided FNA was 88% against the 76% accuracy rate of free-hand FNA. US-guided FNA provides a better representative sample and has a higher diagnostic rate in the evaluation of thyroid lesions.