Species-specific immunocytochemical localization of Mycobacterium tuberculosis complex in fine needle aspirates of tuberculous lymphadenitis using antibody to 38 kDa immunodominant protein antigen

OBJECTIVE: To examine immunocytochemical localization of Mycobacterium tuberculosis (MTB) complex antigen in fine needle aspiration (FNA) smears of tuberculous lymphadenitis (TBLN) using species-specific monoclonal antibody MTSS to 38-kDa immnunodominant protein antigen as a diagnostic adjunct to conventional cytomorphology and its advantage over Ziehl-Neelsen (ZN) microscopy. Study Design FNA smears from 340 cases-174 TBLN; 34 negative controls from nontuberculous, positive controls of 13 known acid-fast bacilli (AFB)-positive sputum smears; 50 blind controls; and 69 other controls (smears from stock cultures of bacterial, atypical mycobacteria and fungal species) were subjected to ZN and immunocytochemical staining using MTSS by the streptavidin-biotin method. RESULTS: Immunocytochemical staining was positive in 59 of 61 (96.7%) archival and 110 of 113 (97.3%) fresh FNA smears; ZN positivity for AFB was observed in 27 of 61 (44.2%) archival and 48 of 113 (42.4%) fresh FNA smears of TBLN. CONCLUSION: The immunostaining using MTSS showed a definite advantage over conventional ZN staining for detection and specific diagnosis of TBLN in FNA smears with 0% false positive results. Immunostaining of cytosmears with species specific antibody to MTB would prove to be a good diagnostic adjunct to morphologic diagnosis.     

Utility of papanicolaou stain-induced fluorescence in the cytodiagnosis of extrapulmonary tuberculosis

OBJECTIVE: To study the utility of Papanicolaou stain-induced fluorescence (PIF) in the detection of tubercle bacilli and to compare its diagnostic efficacy with that of the conventional Ziehl-Neelsen (ZN) method. STUDY DESIGN: This prospective study was carried out at a tertiary health care center, over a period of 2 years between January 2001 and December 2002. A total of 500 cases offine needle aspiration cytology from lymph nodes and other extrapulmonary sites were studied. Only cases that were clinically and cytologically suggestive of tuberculosis were included in the study. The smears were stained with ZN and Papanicolaou stain and examined under light and fluorescence microscopes, respectively for detection of acid-fast bacilli (AFB). Mycobacterial culture was used as the gold standard to compare the results. RESULTS: Cytologic smears were categorized into 4 distinct cytomorphologic patterns: epithelioid granulomas without caseous necrosis (101 cases), epithelioid granulomas with caseous necrosis (268 cases), caseation or acute inflammatory exudate only (114 cases), and occasional epithelioid cells without necrosis or giant cells (17 cases). The overall AFB positivity was 30.8% with the ZN method, while it was 40.6% with PIF. Moreover, PIF was more effective in detecting bacilli in group I lesions (18.8% vs. 6.9% with ZN method), in which the bacillary load is very low. CONCLUSION: PIF is superior to the conventional ZN method in detecting tubercle bacilli, particularly when the bacillary load is low. It is a relatively inexpensive and fast technique.     

Nucleic acid amplification of Mycobacterium tuberculosis complex DNA from archival fine needle aspiration smear scrapings vs. fresh fine needle aspirates of tuberculous lymphadenitis

OBJECTIVE: To assess the efficacy of the nucleic acid amplification (NAA) technique for Mycobacterium tuberculosis (MTB) complex from archival fine needle aspirate (FNA) smear scrapings of confirmed cases of extrapulmonary tuberculosis (EPTB) for a retrospective diagnosis of EPTB as compared to NAA from fresh FNA material from the same cases. STUDY DESIGN: Smear scrapings from 51 cases; 33 cases of tuberculous lymphadenitis (from patients who had undergone NAA 1 year before for MTB from fresh FNA material); 13 negative controls from nontuberculous, archival FNA smears; and 5 known acid-fast bacilli (AFB)-positive sputum smears, were subjected to NAA using the IS6110 primer sequence of M tuberculosis. Ziehl-Neelsen staining was done in all the smears. RESULTS: Of the 33 cases of tuberculous lymphadenitis, 15 (45.4%) were AFB positive and 18 (64.5%) AFB negative. MTB NAA was positive in 73.3% (11 of 15 AFB-positive cases) in the freshly aspirated material and was observed in 60% (9 of 15 AFB-positive cases) when done on DNA extracted from the archival smear scrapings of the same cases. Similarly, in the 18 AFB-negative cases, MTB NAA positivity was 72.2% (13 of 18) on fresh material and 44.4% (8 of 18) on archival smear scrapings from the same AFB-negative cases. Overall NAA positivity was 51.5% for archival smear scrapings as compared to 71% for fresh FNA of the same cases. CONCLUSION: Low NAA sensitivity of MTB DNA in archival material of known tuberculous cases limits the routine use of NAA based retrospective molecular diagnosis of MTB complex.     

Fine needle aspiration cytology of suspected tuberculous lymphadenitis

Fine needle aspiration cytology of suspected tuberculous lymphadenitis The aims of this cross-sectional study were to describe the distributional patterns of tuberculous lymphadenitis and to assess the correlation between fine needle aspiration cytology (FNAC) and the Ziehl Neelsen staining technique in diagnosing tuberculous lymphadenitis. Romanowsky's method (Wright's stain) for cytological diagnosis and Ziehl Neelsen (hot method) for the identification of acid-fast bacilli were utilized. Out of one hundred and twenty-eight consecutive patients attending the cytological diagnostic service of the Department of Pathology within Jimma University, 89 (69.6%) of the patients were younger than 30 years of age. The male to female ratio was 1.3 : 1. The cervical region was the most common site and involved 95 cases (74.2%), followed by the axillary and inguinal lymph node regions (20.3% and 4.3%, respectively). The Wright's-stained cytology smears were grouped into three categories: epithelioid granulomas without necrosis, epithelioid granulomas with caseous necrosis and necrosis without epithelioid granulomas. The Ziehl Neelsen stains were undertaken on separate slides: 20.0% of the cases showing epithelioid granulomas without necrosis, 61.9% of those with epithelioid granulomas with necrosis/abscesses and 69.7% of those with necrosis without granulomas were found to be positive for acid-fast bacilli. The overall positivity for the ZiehlNeelsen stained cases was 59.4%. It can therefore be concluded that FNAC is a reliable diagnostic tool in helping to avert the more invasive surgical procedures undertaken in the diagnosis of tuberculous adenitis. The ZiehlNeelsen stain for identification of acid-fast bacilli should be incorporated as an adjunct to increase the diagnostic accuracy of tuberculous lymphadenitis.     

Concentration of Lymph Node Aspirate Improves the Sensitivity of Acid Fast Smear Microscopy for the Diagnosis of Tuberculous Lymphadenitis in Jimma,Southwest Ethiopia

Background

Tuberculous lymphadenitis (TBLN) is the most common form of extrapulmonary tuberculosis. The cytomorphological features of lymph node smears have reduced specificity for the diagnosis of tuberculosis. The diagnosis of TBLN with direct smear microscopy lacks sensitivity due to the limited number of bacilli in lymph node aspirate. Therefore, we aimed to assess whether the concentration of lymph node aspirate improves the sensitivity of acid fast smear microscopy for the diagnosis of tuberculous lymphadenitis.

Methods

A cross-sectional comparative study was conducted on 200 patients clinically suspected for tuberculous lymphadenitis in Jimma, Ethiopia. Lymph node aspirate was collected. The first two drops were used for cytomorphological study and direct acid fast staining. The remaining aspirate was treated with N-acetyl-L-cysteine (NALC) and concentrated by centrifugation at 3000 g for 15 minutes. The sediment was used for acid fast staining and culture. Differentiation of M. tuberculosis complex (MTBC) from non-tuberculous mycobacteria (NTM) was done by para-nitrobenzoic acid susceptibility test.

Result

Complete data were available for 187 study subjects. 68% (127/187) were positive for M. tuberculosis on culture. Four isolates, 2.1% (4/187), were identified as NTM. The detection rate of direct smear microscopy was 25.1% and that of the concentration method 49.7%. Cytomorphologically, 79.7% of cases were classified as TBLN. The sensitivity of direct smear microscopy was 34.6%, for concentrated smear microscopy 66.1%, and for cytomorphology 89.8%. Two AFB positive cases on concentration method were non-tuberculosis mycobacteria (NTM). The concentration method yielded a positive result from seven cases diagnosed as suppurative abscess by cytology. Both for the direct and concentration methods the highest rate of AFB positivity was observed in smears showing caseous necrosis alone. Smear positivity rate decreased with the appearance of epithelioid cell aggregates.

Conclusion

The concentration of lymph node aspirates for acid fast smear microscopy had significantly higher sensitivity than direct microscopy.     

Polymerase chain reaction vs. conventional diagnosis in fine needle aspirates of tuberculous lymph nodes

OBJECTIVE: To compare four conventional methods of diagnosing tuberculous lymphadenophathy (TL)--namely fine needle aspiration cytology (FNAC), Zeihl-Neelsen staining of smears for acid-fast bacilli (AFB), culture for Mycobacterium tuberculosis (MTB) and lymph node biopsies--with the polymerase chain reaction (PCR) in order to assess the practicability and advantage of its use in routine diagnosis in a developing country. STUDY DESIGN: Fine needle aspirates from 142 consecutive patients presenting with lymphadenopathy (mainly cervical) without any known systemic involvement underwent cytomorphologic diagnosis, AFB smears, culture for MTB, confirmatory biopsy and PCR for MTB. The aspirates from cases other than TL served as controls for PCR. RESULTS: Correct diagnosis of tuberculosis could be made in 94.87% of cases by a combination of the four methods. PCR was done in 52 cases, 39 confirmed TL and 13 controls. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value of PCR were 94.44%, 38.23%, 44.73% and 92.85%, respectively, when culture alone was considered the gold standard. However, specificity (38.23-92.30%) and PPV (44.73-97.36%) of PCR increased remarkably when response to treatment was taken as the final arbiter. CONCLUSION: The four conventional tests were found to be the methods of choice for the diagnosis of TL in developing countries. PCR should be reserved for problem cases.     

Fine needle aspiration diagnosis in HIV-related lymphadenopathy in Mangalore, India

OBJECTIVE: To evaluate the usefulness of fine needle aspiration (FNA) study of lymph nodes in HIV-positive patients. STUDY DESIGN: The study was conducted at Kasturba Medical College, Mangalore, India. Samples from lymph nodes of 48 HIV-positive patients were taken and air dried, and wet smears were made. After staining with routine cytologic stains and special stains, detailed cytomorphologic study was conducted. RESULTS: Tuberculosis accounted for nearly half (48%) the cases,followed by HIV lymphadenitis (36%), lymphoma (10%), suppurative lymphadenitis (2%), Mycobacterium avium-intracellulare lymphadenitis (2%) and metastases (2%), in descending order of their frequency. A suppurative picture, which was found in 13% of cases of tuberculous lymphadenitis in AIDS patients, occasionally was misleading without the help of acid fast bacilli stain. CONCLUSION: FNA is a useful tool in the diagnosis of lymphadenopathy in HIV-positive patients provided that proper safety measures are taken to avoid contracting the infection.     

Critical appraisal of fine needle aspiration cytology in tuberculous lymphadenitis.

A cytomorphologic diagnosis of tuberculous lymphadenitis by examination of needle aspirates was made in 560 of 1,471 cases of lymphadenopathy studied over two years. Cytologic features were categorized into four groups: epithelioid clusters with or without Langhans's giant cells without necrosis (32.14%), epithelioid clusters with or without Langhans's giant cells with necrosis (50.35%), occasional epithelioid cells without characteristic necrosis/giant cells (2.85%) and necrosis without epithelioid clusters or Langhans's giant cells (14.64%). While a diagnosis of tuberculous lymphadenitis was offered with confidence in the first two groups, constituting about 82.49% cases, aspirates from the third- and fourth-group patients were subjected to Ziehl-Neelsen staining for acid-fast bacilli, which was positive in 12.5% and 75.6% of cases, respectively.     

A sensitive and specific ES-31 antigen detection based fluorometric assay for confirmation of Mycobacterium tuberculosis in cell culture

Confirmation of presence of M. tuberculosis bacilli on microscopic examination is very important in diagnosis of tuberculosis. The present study was undertaken to find the usefulness of mycobacterial ES-31 serine protease as a marker to detect tuberculosis bacilli using fluorescein isothiocyanate conjugated anti-ES-31 serine protease antibody. This immunofluorescence method was compared with Ziehl-Neelsen and auramine-O staining methods for detection of tuberculosis bacilli. Slides were prepared for each serially diluted tuberculosis H37Ra bacilli (1 x 10(7) bacilli/ml to 5 bacilli/ml). Slides for each dilution group were stained by ZN method, auramine-O and immunostaining methods using fluorescein isothiocyanate conjugated anti-ES-31 serine protease antibody. ZN staining method showed efficacy for detection of M. tuberculosis H37Ra upto 1 x 10(4) bacilli/ml while auramine-O method showed upto 1 x 10(2) bacilli/ml. The presence of bacilli was indicated by green fluorescence on immunostaining using anti-ES-31 antibody conjugate and this method was effective upto 10 bacilli/ml. The slides which were negative for ZN (1 x 10(3) cells/ml) and auramine-O (100 cells/ml) method showed positivity on restaining with immunofluorescent staining method. The results of this preliminary study showed that immunofluorescent staining method using specific anti-ES-31 antibody conjugate was more sensitive for detection of tuberculosis bacilli than ZN and auramine-O methods in samples of laboratory strain. The utility of this method will be studied further in clinical specimens.     

Fine needle aspiration cytology in HIV‐related lymphadenopathy: experience at a single centre in north India

P. K. Sarma, A. K. Chowhan, V. Agrawal and V. Agarwal
Fine needle aspiration cytology in HIV‐related lymphadenopathy: experience at a single centre in north India Objective: Fine needle aspiration (FNA) is emerging as a rapid and minimally invasive tool in evaluating lymphadenopathy associated with human immunodeficiency virus (HIV). We evaluated the role of FNA in differentiating various causes of lymphadenopathy in patients with HIV and correlated the cytological diagnosis with CD4 counts. Methods: Seventy‐nine HIV‐positive patients (median age 35 years, 68 male) underwent ultrasound‐guided (n = 16) and unguided (n = 63) FNA from 1999 to 2006. Smears were stained with May–Grünwald–Giemsa, haematoxylin & eosin and Papanicolaou stains. Ziehl–Neelsen (ZN) staining for acid‐fast bacilli (AFB) was performed in all cases. Staining for fungus was performed whenever required. Results: The aspirates were adequate in 75 cases (95%). Non‐specific reactive hyperplasia was the most common FNA diagnosis (39, 52%) followed by granulomatous necrotizing lymphadenitis (15, 20%), necrotizing lymphadenitis (13, 17.3%) and granulomatous lymphadenitis (4, 5.2%). Fungal infection and non‐Hodgkin lymphoma (NHL) were seen in two patients each. ZN staining was positive for AFB in 25 (33.3%) cases. One of these was morphologically interpreted as reactive hyperplasia, 12 as necrotizing lymphadenitis and 12 as granulomatous necrotizing lymphadenitis. Both patients with NHL had CD4 counts below 100/dl. Necrotizing lymphadenitis and granulomatous lymphadenitis were significantly associated with CD4 counts below and above 200/dl, respectively (P = 0.0002). Conclusions: FNA is an important tool for assessing the cause of lymphadenopathy in HIV patients. Necrotizing inflammation is more often seen in patients with low CD4 counts. AFB are commonly found in necrotic aspirates with or without granulomas. However, a stain for AFB should be performed in all aspirates from HIV‐related lymphadenopathy including reactive hyperplasia.     

Tuberculosis of the breast. A cytomorphologic study

OBJECTIVE: Extrapulmonary tuberculosis occurring in the breast is rare despite the fact that 1-2 billion people worldwide suffer from tuberculosis. The aim of this study was to examine the cytomorphology of breast tuberculosis (breast TB) and to review the literature. STUDY DESIGN: Old records from the Cytopathology Laboratory, All India Institute of Medical Sciences, were reviewed from January 1980 to December 1998. Cases of breast TB where a cytologic diagnosis was rendered or a histologic diagnosis with prior fine needle aspiration cytology (FNAC) was available were selected. These slides were reviewed for determining the cytologic findings. RESULTS: One hundred sixty cases of breast TB were included in the study. Six males and 154 females with a clinical suspicion of carcinoma had undergone FNA that was reported as TB. The majority of the patients (111) were in the reproductive age group, 21-40 years. Of the 160 cases, 118 (73.75%) had cytomorphology diagnostic of tuberculosis--epithelioid cell granulomas with caseous necrosis. Eleven of the remaining 42 cases were positive for acid-fast bacilli (AFB) on Ziehl-Neelsen (ZN) staining, while 31 cases were confirmed to be tubercular on histology. ZN staining was done in 44 cases, and AFB were demonstrated in only 38.6% of cases. CONCLUSION: Up to 73% of breast TB can be confidently diagnosed when both epithelioid cell granulomas and necrosis are present. Also, the possibility that a woman in the reproductive age group who presents with a palpable lump in the breast may have tuberculosis must be kept in mind, especially as the incidence of breast TB may increase in the future with the global spread of AIDS.     

Superficial mycobacterial lymphadenitis in Saskatchewan.

A total of 43 bacteriologically verified cases of superficial mycobacterial lymphadenitis were reported in Saskatchewan between 1981 and 1986; 35 (81%) were due to Mycobacterium tuberculosis. Among the eight cases (19%) due to nontuberculous mycobacteria the agent most frequently isolated was M. avium-intracellulare. Five additional cases were smear-positive and culture-negative. Direct smears of node tissue or aspirate were positive for acid-fast bacilli in 7 (88%) of the 8 cases of nontuberculous mycobacterial lymphadenitis but in only 16 (46%) of the 35 cases due to M. tuberculosis. Superficial tuberculous lymphadenitis was most frequent in female North American Indian or Asian-born adults and most commonly involved the cervical nodes. Nontuberculous mycobacterial lymphadenitis was most frequent in female white children, and most commonly involved the submandibular nodes. The cases of both tuberculous and nontuberculous mycobacterial lymphadenitis were spread throughout the province. There was an urban concentration of cases of tuberculous lymphadenitis in those of Asian origin. It is important to distinguish between superficial mycobacterial lymphadenitis due to M. tuberculosis and that due to nontuberculous mycobacteria for treatment and management purposes.     

Zoonotic transmission of tuberculosis between pastoralists and their livestock in South-East Ethiopia

Despite huge global efforts in tuberculosis (TB) control, pastoral areas remain under-investigated. During two years sputum and fine needle aspirate (FNA) specimens were collected from 260 Ethiopian pastoralists of Oromia and Somali Regional States with suspected pulmonary TB and from 32 cases with suspected TB lymphadenitis. In parallel, 207 suspected tuberculous lesions were collected from cattle, camels and goats at abattoirs. All specimens were processed and cultured for mycobacteria; samples with acid-fast stained bacilli (AFB) were further characterized by molecular methods including genus and deletion typing as well as spoligotyping. Non-tuberculous mycobacteria (NTM) were sequenced at the 16S rDNA locus. Culturing of AFB from human sputum and FNA samples gave a yield of 174 (67%) and 9 (28%) isolates, respectively. Molecular typing was performed on 173 of these isolates and 160 were confirmed as Mycobacterium tuberculosis, three as M. bovis, and the remaining 10 were typed as NTMs. Similarly, 48 AFB isolates (23%) yielded from tuberculous lesions of livestock, of which 39 were molecular typed, including 24 M. bovis and 4 NTMs from cattle, 1 M. tuberculosis and 1 NTM from camels and 9 NTMs from goats. Isolation of M. bovis from humans and M. tuberculosis from livestock suggests transmission between livestock and humans in the pastoral areas of South-East Ethiopia.     

Fine needle aspiration cytology in the diagnosis of tuberculous mastitis

OBJECTIVE: To study the relationship between granulomas in the breast and tuberculous mastitis. STUDY DESIGN: Retrospective analysis of 22 breast aspirates that showed epithelioid cell granulomas. The aspirates were reviewed and the cytomorphologic findings summarized. RESULTS: Aspiration cytology revealed epithelioid cell granulomas along with giant cells, necrosis and inflammatory cell infiltrate. Overall acid-fast bacillus (AFB) positivity was 22.7%. AFB positivity was greater in the presence of necrosis when epithelioid cells were absent. CONCLUSION: In a country like India, the diagnosis of granulomatous mastitis must be made with caution, even in the absence of AFB. Only after a sufficient trial of antituberculosis treatment has been given and the patient fails to respond should an alternative diagnosis be suggested.     

Fine needle aspiration cytology and immunocytochemistry in tuberculous thyroiditis: a case report

BACKGROUND: Tuberculosis of the thyroid is very rare and does not strike the clinician as a first clinical diagnosis of a thyroid nodule. To our knowledge, only 40 cases of tuberculous thyroiditis diagnosed by fine needle aspiration cytology (FNAC) are described in the English literature. CASE: We report a case of tuberculous thyroiditis in a young woman who presented with a right-side solitary thyroid nodule of short duration (15 days), diagnosed by FNAC and confirmed by positive immunocytochemistry with monoclonal antibody to Mycobacterium tuberculosis complex. Ziehl Neelsen staining for acid-fast bacilli (AFB) was negative. CONCLUSION: FNAC provides a confident preoperative diagnosis of thyroid tuberculosis, obviating the need for unnecessary surgical removal of thyroid nodule. Immunocytochemistry is an important diagnostic adjunct to FNAC in AFB-negative cases.     

Tuberculosis of the intercostal lymph nodes

OBJECTIVE: To describe tuberculosis of the intercostal lymph nodes and discuss its clinical and cytologic profile and pathogenesis. STUDY DESIGN: Fifteen cases from March 1994 to March 2000 were retrieved from our cytology records. Only clinically and therapeutically proven cases were included in the study. RESULTS: The ages of the patients ranged from 4 to 63 years. The male:female ratio was 2:1. The duration of disease at presentation ranged from one week to nine months. The lumps presented either in the parasternal region or between the midclavicular and posterior axillary lines. One case presented with an infrascapular lump. Most of the lumps were ill defined and cystic. Chest radiographs in all cases showed a soft tissue swelling without bony involvement. The aspirates were of two types, blood-mixed particles and necrotic material. Four cytologic pictures were seen: (1) epithelioid cell granulomas alone or (2) with necrosis or (3) with both necrosis and acid-fast bacilli (AFB), or (4) necrosis with AFB. AFB were detected in 53.3% of cases. CONCLUSION: If necrotic material is aspirated or if granulomatous inflammation is encountered in soft tissue swellings of the chest wall, particularly in the parasternal and axillary regions, the possibility of intercostal tuberculous lymphadenitis should be considered.     

A comparative study on the different staining methods and number of specimens for the detection of acid fast bacilli

The presence of acid fast bacilli in multiple specimens was investigated comparatively with Ziehl-Neelsen (ZN) and fluorescence microscopy (FM) staining in order to determine sensitivity in detecting tuberculosis (TB). A total of 465 specimens obtained from 295 patients were analysed at Harran University Medical School Hospital between March 1998 and March 2000. The culture was employed as the reference method. Sixty-eight patients (23.1%) were diagnosed as having TB by culture. The ZN and FM staining sensitivities were 67.6% (46/68) and 85.2% (58/68) respectively. Two hundred and one patients (68.1%) submitted one specimen to the laboratory. TB positivity was detected in 42 (20.9%) of these patients by culture. The sensitivities of ZN and FM stains were found to be 61% and 83% in these patients. However, in 18 patients (6.1%) who submitted two specimens to the laboratory, the TB was positive in six of them (33.3%) and ZN and FM sensitivities were 66% and 83% respectively. When three specimens or more were collected from the patients (76 patients, 25.8%), TB positivity was determined in 20 of them (26.3%) and the sensitivities were 80% and 92% in the ZN- and FM-stained smears, respectively. Our data indicate that in the diagnosis of TB, FM has greater sensitivity than ZN. In particular, in the case of a single specimen, the diagnostic value of FM is quite significant. It is, therefore, possible to conclude that both ZN and FM staining can be used for the diagnosis of TB when there are more than two specimens. However, if only one or two specimens are available, FM staining is preferable.     

Tubercular dactylitis: Fine needle aspiration cytology as a diagnostic modality

OBJECTIVE: To evaluate the efficacy of aspiration cytology in the early diagnosis of tuberculous dactylitis and describe the spectrum of cytomorphologic features in these cases. STUDY DESIGN: We studied 12 cases of dactylitis diagnosed as of tubercular etiology by fine needle aspiration cytology (FNAC) over a period of 6 years and assessed the clinicoradiologic features. The stained slides were reviewed and the spectrum of features noted. RESULTS: The most common clinical presentation was an indurated swelling of the involved digit (100%). On radiography, most often an expansile, lytic lesion along with soft tissue swelling was noted in 83% of cases. However, the clinical diagnosis did not consider a tubercular (TB) etiology. FNAC of these cases showed variable features; the most common was granulomas with or without necrosis (75% in total). Two cases showed acute suppurative cytology, and 1 revealed only fibroblasts and afew neutrophils. On the basis of suspicion, staining for acid-fast bacilli (AFB) was done in all cases, and bacilli were identified in all of them after a thorough search. These patients were soon started on antituberculous therapy, with significant improvements. CONCLUSION: FNAC can serve as an inexpensive and comparatively less invasive procedure for early diagnosis of TB dactylitis, permitting timely initiation of specific therapy. This study also highlighted the unusual cytomorphology in some cases. Clinicians and pathologists should maintain a high index of suspicion in cases of dactylitis and stain for AFB in all cases.     

Caseous, necrotic material and epithelioid cell granulomas in synovial fluid from a patient with tuberculous infection: a case report

BACKGROUND: The gross appearance and cytologic findings in synovial fluid in tuberculous infections are similar to those in other types of chronic synovial effusion. Demonstration of acid-fast bacilli (AFB) is required for a definitive diagnosis of tuberculous effusion; it is reported in only 20% of cases. The presence of frank caseous necrotic material and epithelioid cell granulomas in synovial fluid samples is unusual but strongly indicative of tuberculous infection. CASE: A 28-year-old man, on treatment for pulmonary tuberculosis, presented with a history of right ankle swelling, which was clinically interpreted as nonspecific synovitis. The synovial fluid was yellowish, with fluffy, whitish material. Cytologic smears showed abundant, caseous, necrotic material; a few histiocytic aggregates; and occasional epithelioid cell granulomas. Although stain for AFB was negative, considering the clinical presentation, a diagnosis of tuberculous synovitis could be rendered. CONCLUSION: Caseous, necrotic material and epithelioid granulomas in synovial fluid are highly unusual but, when present, can be considered definitive evidence of tuberculous effusion, particularly in a known case of pulmonary tuberculosis.     

Correlation between culture of Mycobacterium tuberculosis and antimycobacterial antibody in lumbar, ventricular and cisternal cerebrospinal fluids of patients with tuberculous meningitis.

In this study positive culture for M. tuberculosis were obtained, 20% in lumbar cerebrospinal fluid (CSF), 75% in ventricular CSF and 87.5% in cisternal CSFs of patients with tuberculous meningitis. Low culture positivity in lumbar CSF is due to the low density of circulating tubercle bacilli in lumbar CSF than in cisternal or ventricular CSFs. However antimycobacterial antibody in lumbar, cisternal and ventricular CSFs circulate in significant titres and are not statistically different from one another. Since specimens of CSF can not be obtained from cisternal or ventricular routes for the routine bacteriological investigations in patients with tuberculous meningitis, detection of antimycobacterial antibody of M. tuberculosis antigen 5 in lumbar CSF by an indirect ELISA may be considered as an aid for the diagnosis of tuberculous meningitis, particularly when repeated CSF cultures are negative for M. tuberculosis.