Pancreatic tuberculosis: A systematic review of symptoms, diagnosis and treatment.

INTRODUCTION: Although pancreatic tuberculosis (TB) is traditionally considered to be a rare clinical entity, in recent times, an increase in the number of reports of pancreatic TB has been noted. We conducted a systematic review in order to summarise currently available data on pancreatic TB. METHODS: A comprehensive literature search of Medline, Scopus and ISI Web of Science databases was conducted in order to identify papers reporting cases of pancreatic TB. The eligibility criteria for inclusion in the review required that the studies reported patient(s) affected by pancreatic TB and that individual data on age, sex, clinical presentation and outcome were available. RESULTS: In total, 116 studies reporting data on 166 patients were included in the analysis. The majority of patients were males (62.1%) diagnosed at a mean age of 41.61 ± 13.95 years. Most cases were diagnosed in Asia (50.0%), followed by North America (22.9%), Europe (20.5%), Africa (4.2%) and South America (2.4%). Human immunodeficiency virus (HIV) infection was diagnosed in 25.3% of those affected. Pancreatic TB most frequently presented itself in the form of a pancreatic mass (79.5%) localised mainly in the head (59.0%) and less frequently in the body (18.2%) and tail (13.4%). Extrapancreatic TB involvement most frequently affected the peripancreatic lymph nodes (47.3%). More than half of patients (55.2%) were subjected to laparotomy, while 21.08% underwent endoscopic ultrasound fine-needle aspiration biopsy. The presence of TB was identified most frequently through histological analysis (59.6%), followed by culture (28.9%), staining (27.7%) and, in a smaller number, by polymerase chain reaction (9.6%) and cytology (6.6%). Almost all patients received anti-tubercular pharmacological therapy (98.2%), while 24.1% underwent surgery. Despite treatment, 8.7% of patients died. CONCLUSION: Increased awareness of pancreatic TB is needed, not only in endemic areas but especially in relation to HIV infection and other clinical conditions associated with immunoincompetence.

Assessment of Clinically Suspected Tubercular Lymphadenopathy by Real-Time PCR Compared to Non-Molecular Methods on Lymph Node Aspirates.

BACKGROUND: The diagnosis of tubercular lymphadenitis (TBLN) is challenging. This study assesses the role of diagnostic intervention with real-time PCR in clinically suspected tubercular lymphadenopathy in relation to cytology and microbiological methods. METHODS: The cross-sectional study involved 214 patients, and PCR, cytology, and Ziehl-Neelsen (ZN) staining was performed on aspirates. The findings were compared with culture on Lowenstein-Jensen medium. The overall concordance of cytology and PCR, both individually and combined, was calculated. χ2 and Phi values were assessed between cytology, PCR, and culture. RESULTS: A cytological diagnosis of tuberculosis (TB), reactive lymphoid hyperplasia, and suppurative lymphadenitis was made in 71, 112, and 6 patients, respectively. PCR and culture were positive in 40% of the cases. Among the TBLN patients, PCR showed higher positivity in necrosis and culture showed higher positivity in necrotizing granuloma. Positive ZN staining was observed in 29.6% of the TBLN cases, with an overall positivity of 11%. PCR could additionally detect 82 cases missed by ZN staining. The overall concordance rate for either diagnostic modality, i.e., PCR or cytology, was highest (75%), and for PCR alone was 74%. Phi values were observed to be 0.47 between PCR and culture. CONCLUSION: Real-time PCR for Mycobacterium tuberculosis complex on aspirates offers a definitive and comparable diagnosis of TBLN. Including this approach as the primary investigation in the work-up of TBLN could reduce the burden of TB.

The use of light-emitting diode fluorescence to diagnose mycobacterial lymphadenitis in fine-needle aspirates from children.

BACKGROUND: Fine-needle aspiration biopsy (FNAB) is a simple, safe and effective method for investigating suspected mycobacterial lymphadenitis in children. Fluorescence microscopy can provide rapid mycobacterial confirmation. Light-emitting diodes (LEDs) provide a cheap and robust excitation light source, making fluorescence microscopy feasible in resource-limited settings. OBJECTIVE: To compare the diagnostic performance of LED fluorescence microscopy on Papanicolaou (PAP) stained smears with the conventional mercury vapour lamp (MVL). METHODS: FNAB smears routinely collected from palpable lymph nodes in children with suspected mycobacterial disease were PAP-stained and evaluated by two independent microscopists using different excitatory light sources (MVL and LED). Mycobacterial culture results provided the reference standard. A manually rechargeable battery-powered LED power source was evaluated in a random subset. RESULTS: We evaluated 182 FNAB smears from 121 children (median age 31 months, interquartile range 10-67). Mycobacterial cultures were positive in 84 of 121 (69%) children. The mean sensitivity with LED (mains-powered), LED (rechargeable battery-powered) and MVL was respectively 48.2%, 50.0% and 51.8% (specificity 78.4%, 86.7% and 78.4%). Inter-observer variation was similar for LED and MVL (κ = 0.5). CONCLUSION: LED fluorescence microscopy provides a reliable alternative to conventional methods and has many favourable attributes that would facilitate improved, decentralised diagnostic services.

Thoracoscopic assessment of mediastinal tuberculous lymphadenitis in a 4-month-old child.

Isolated mediastinal tuberculous lymphadenitis is a relatively common entity in children, second in frequency after cervical localization. In the absence of an accompanying parenchymal lesion, mediastinal tuberculous lymphadenitis may pose a diagnostic dilemma on admission and must be distinguished from other causes of mediastinal masses. Bronchoscopy is suggested as a diagnostic tool where tuberculosis cannot be excluded by radiology or specific skin tests. Thoracotomy and excision is reported as necessary to treat the obstructive symptoms. In this report, the diagnostic and therapeutic feasibility of thoracoscopic mediastinal node biopsy in a 4-month-old presenting mediastinal tuberculous lymphadenitis is reported.

A technically simple method for staining of acid-fast bacilli in cytology smears: an evaluation.

OBJECTIVE: To study the effects of modifications in the Ziehl-Neelsen staining procedure on predictive accuracy for acid fast bacilli in comparison to the conventional technique. Simplicity of procedure and reagent economy were the factors taken into consideration. DESIGN: Comparative evaluation between thick and thin air-dried smears stained conventionally and thick ethanol-fixed smears stained by the modified technique was done. RESULTS: Positive predictive accuracy of all the three smears, that is, thick air-dried, thin air-dried and thick ethanol-fixed, was 100%. Negative predictive accuracy for thick air-dried, thin air-dried and thick ethanol-fixed smears was 36.36%, 32.33% and 34.78%, respectively. Overall predictive accuracy was 66.67% for thick air-dried, 61.90% for thin air-dried and 64.29% for thick ethanol-fixed. These differences were found to be statistically insignificant. CONCLUSION: The modified method offers an accuracy comparable to the conventional technique, is simpler and with improved reagent economy. It is of special importance to diagnostic facilities in rural set-ups.

Assessment of possible tuberculous lymphadenopathy by PCR compared to non-molecular methods.

Tuberculosis is a major public health problem in India and other developing countries and has formed a lethal partnership with AIDS. It often presents a diagnostic challenge especially when clinical presentation is suggestive but bacteriological proof is lacking. The objective of this study was to compare the various diagnostic techniques in clinically suspected cases of tubercular lymph nodes and to find a suitable, cost-effective but sensitive and specific method for diagnosis. A total of 100 cases were recruited for the study. Fine needle aspiration cytology was done in all cases and the smears prepared were processed for Giemsa, Ziehl-Neelsen's, Kinyoun and Papanicolaou stains. Parts of the aspirated materials were assessed by fluorescent staining, culture and PCR. Seventy-four percent of aspirates were positive by fluorescent stain while only 22% were positive by culture. PCR could be performed in 55 cases, out of which 22 (40%) were positive. When compared to culture, the sensitivity and specificity of PCR were found to be 89.5% and 86.1%, respectively. Fluorescent stain was found to be the most sensitive (81.8%) of the conventional methods but showed poor specificity (28.2%). Interestingly, PCR detected 80% of smear-negative but culture-positive cases.

Aspiration cytology for diagnosis of tuberculosis--perspectives in India.

Tuberculosis (TB) a common cause of mortality can readily be diagnosed by fine needle aspiration. The technique is a simple, cost effective, out patient procedure with a high diagnostic accuracy both in adults and children. The diagnostic morphologic findings comprise of epithelioid cell granulomas and giant cells with or without necrosis. Often an acute inflammatory exudate is obtained. Stain for acid fast bacilli immensely augments diagnosis especially in cases where necrosis or an inflammatory exudate is obtained. Culture studies on aspirated material are time consuming though diagnosis is enhanced. PCR can be applied to detect mycobacterial DNA and has been applied on aspirated material and found to be more sensitive in the detection of tuberculosis. In children TB of lymph nodes is readily identified and so also from other sites such as bone and soft tissues. In children FNAC also plays a role in detection of BCG adenitis, infection with atypical mycobacteria and co-existing infections such as HIV and AIDS.

Mycobacterial cervical lymphadenitis in children: can histological assessment help differentiate infections caused by non-tuberculous mycobacteria from Mycobacterium tuberculosis?

Most mycobacterial lymphadenitis in children in developed countries is caused by non-tuberculous (the so-called 'atypical') mycobacteria. In view of the widely different treatment regimes and the requirement for contact tracing in Mycobacterium tuberculosis infections but not in non-tuberculous mycobacterial infections, it is very important to attempt to define histologically which is the aetiological agent. We have reviewed the histological appearances of mycobacterial cervical lymphadenitis in children and have found that, if any one of several 'atypical' features were seen, the appearances were much more likely to be due to a non-tuberculous mycobacterium. These features include ill-defined (non-palisading) granulomas, irregular or serpiginous granulomas, a predominantly non-specific granulomatous response, predominantly sarcoid-like granulomas or lack of significant caseation. In addition, the non-tuberculous mycobacterial infections showed a different distribution of neutrophil polymorphs, which tended to be seen in the centre of areas of necrosis rather than in Mycobacterium tuberculosis infections where a polymorph infiltrate, if present, was more diffusely scattered. Although no one definitive feature is diagnostic of non-tuberculous mycobacterial infection, some features are helpful in differentiating the two groups of organisms histologically.