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.     

FNAC of Bacillus- Calmette- Guerin lymphadenitis masquerading as Langerhans cell histiocytosis

Bacillus Calmette Guerin (BCG) lymphadenitis is a well known entity. Disseminated BCG infection usually presents as generalized lymphadenopathy, skin rash and hepatosplenomegaly and at times, can pose a diagnostic challenge to clinicians. There are only a few published studies on the cytological findings of BCG lymphadenitis. In this letter we report the fine needle aspiration cytology (FNAC) of BCG lymphadenitis clinically masquerading as Langerhans cell histiocytosis (LCH). FNA smears showed sheets of foamy macrophages and many polymorphs in a dirty necrotic background with many macrophages as well as polymorphs showing negatively stained rod like structures within their cytoplasm. Zeihl Neelson stain revealed that these cells were heavily loaded with acid fast bacilli (AFB). In the index case, AFB were also seen within the cytoplasm of polymorphs, which has not been documented earlier in the literature.     

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.     

Fine needle aspiration cytology of lymph nodes in HIV-infected individuals

OBJECTIVE: To assess the role of fine needle aspiration cytology (FNAC) in lymphadenopathy in human immunodeficiency virus-infected individuals (HIVII). STUDY DESIGN: Thirty-nine HIVII presenting with lymphadenopathy at University Hospital, Kuala Lumpur, were subjected to FNAC. Cytologic smears were routinely stained with May-Grünwald-Giemsa stain. Special stains and immunostains were used when necessary. RESULTS: In nine cases, the cytologic appearance was compatible with HIV type A and in one case with HIV type C lymphadenopathy. In 21 cases, acid-fast bacilli (AFB) were demonstrated in the cytologic smears, enabling a diagnosis of mycobacterial lymphadenitis. In one of these cases there was a concomitant infection with Penicillium marneffei that was overlooked on initial cytologic examination. The cause of granulomatous lymphadenitis could not be ascertained in one case, where neither AFB nor any other organisms were demonstrable. Two cases of histoplasma and one of cryptococcal lymphadenitis were diagnosed, as was one high grade non-Hodgkin's lymphoma that could be immunophenotyped on cytologic material. In three cases the aspirates were inadequate for a cytologic diagnosis. CONCLUSION: Lymph node FNAC is a valuable investigative modality in HIVII. Most opportunistic infections (bacterial and fungal) can be correctly identified, and high grade lymphoma can be diagnosed and phenotyped.     

Evaluation of Cobas Amplicor MTB test to detect Mycobacterium tuberculosis in pulmonary and extrapulmonary specimens

Tuberculosis (TB) is one of the major public health problems in the world. Effective control of TB depends on rapid and correct diagnosis and appropriate treatment. The aim of this study was to evaluate the performance of Cobas Amplicor MTB (CA-MTB) test for pulmonary and extrapulmonary specimens isolated in our laboratory. A total of 424 specimens obtained from the suspected TB patients from January 2003 to August 2004 were included in this study. All specimens (173 pulmonary and 251 extrapulmonary specimens) were processed, stained, cultured and assayed using the CA-MTB test for identification of Mycobacterium tuberculosis. The CA-MTB test results were compared to culture and acid-fast staining as gold standard. The sensitivity, specificity, positive and negative predictive values of CA-MTB were determined as 73%, 100%, 100%, and 97% for pulmonary specimens, and 45%, 100%, 100% and 96% for extrapulmonary specimens respectively. The sensitivity of the test for acid-fast bacilli (AFB) smear positive pulmonary and extrapulmonary specimens was 92% and 75%. These results indicate that the CA-MTB is a rapid test for detection of tuberculosis in pulmonary specimens, but does not perform well enough in extrapulmonary specimens.     

Increased Production of IL-4 and IL-12p40 from Bronchoalveolar Lavage Cells Are Biomarkers of Mycobacterium tuberculosis in the Sputum

Background

Tuberculosis (TB) causes 1.45 million deaths annually world wide, the majority of which occur in the developing world. Active TB disease represents immune failure to control latent infection from airborne spread. Acid-fast bacillus (AFB) seen on sputum smear is a biomarker for contagiousness.

Methods

We enrolled 73 tuberculosis patients with extensive infiltrates into a research study using bronchoalveolar lavage (BAL) to sample lung immune cells and assay BAL cell cytokine production. All patients had sputum culture demonstrating Mycobacterium tuberculosis and 59/73 (81%) had AFB identified by microscopy of the sputum. Compared with smear negative patients, smear positive patients at presentation had a higher proportion with smoking history, a higher proportion with temperature >38.5⁰ C, higher BAL cells/ml, lower percent lymphocytes in BAL, higher IL-4 and IL-12p40 in BAL cell supernatants. There was no correlation between AFB smear and other BAL or serum cytokines. Increasing IL-4 was associated with BAL PMN and negatively associated with BAL lymphocytes. Each 10-fold increase in BAL IL-4 and IL-12p40 increased the odds of AFB smear positivity by 7.4 and 2.2-fold, respectively, in a multi-variable logistic model.

Conclusion

Increasing IL-4 and IL-12p40 production by BAL cells are biomarkers for AFB in sputum of patients who present with radiographically advanced TB. They likely reflect less effective immune control of pathways for controlling TB, leading to patients with increased infectiousness.     

Smear positive pulmonary tuberculosis and associated factors among homeless individuals in Dessie and Debre Birhan towns,Northeast Ethiopia

Background

Tuberculosis (TB) remains one of the globe’s deadliest communicable diseases. The homeless individuals are at high risk to acquire TB and multi-drug resistant TB (MDR-TB), because of their poor living conditions and risky behaviors. Tuberculosis and MDR-TB in the homeless individuals can pose a risk to entire communities. However, the magnitude of the problem is not known in Ethiopia. Therefore, the aim of this study was to determine the prevalence and associated factors of smear positive pulmonary TB (PTB) and MDR-TB among homeless individuals in Dessie and Debre Birhan towns, Northeast Ethiopia.

Methods

A community based cross-sectional study design was conducted from September 2014 to June 2015. Using an active screening with cough of ≥2 weeks, 351 TB suspects homeless individuals were participated in this study. Data were collected by using pre-tested and structured questionnaire. Spot-morning-spot sputum sample was collected and examined for acid-fast bacilli (AFB) using fluorescence microscopy by Auramine O staining technique. All AFB positive sputum was further analyzed by GeneXpert for detection of Mycobacterium tuberculosis complex and rifampicin resistant gene. Univariate and multivariate logistic regressions were applied to identify factors associated with smear positive PTB and P value <0.05 was considered as statistically significant.

Results

The prevalence of smear positive PTB was 2.6 % (95 % CI 1.3–5) among TB suspect homeless individuals. Extrapolation of this study finding implies that there were 505 smear positive PTB per 100,000 homeless individuals. All smear positive PTB sputum specimens were further analyzed by GeneXpert assay, the assay confirmed that all were positive for MTBC but none were resistant to RIF or MDR. Smoking cigarette regularly for greater than 5 years (AOR 10.1, 95 % CI 1.1, 97.7), body mass index lower than 18.5 (AOR 6.9, 95 % CI 1.12, 41.1) and HIV infection (AOR 6.8, 95 % CI 1.1, 40.1) were significantly associated with smear positive PTB.

Conclusion

The prevalence of smear positive PTB among TB suspect homeless individuals was 2.6 %. Among smear positive PTB, prevalence of HIV co-infection was very high 5 (55.5 %). Smoking cigarette regularly for greater than 5 years, BMI lower than 18.5 and HIV infection were factors associated with smear positive PTB. Special emphasis is needed for homeless individuals to exert intensive effort to identify undetected TB cases to limit the circulation of the disease into the community.

     

Antigen detection as a point-of-care test for TB: the case of lipoarabinomannan

The limitations of sputum smear microscopy, routine chest radiology for HIV-associated TB and culture-based diagnosis are well recognized, especially in resource-limited settings. The diagnostic accuracy of a new point-of-care lateral-flow urine strip test for lipoarabinomannan (Determine(?) TB-LAM; Alere, MA, USA), which costs US$3.50 per test strip and provides results within 30 min, was evaluated in a cohort of South African patients for HIV-associated TB before starting anti-retroviral therapy in South Africa. Prevalence of culture-positive TB cases was 17.4%, among which 28.2% had sputum smear positivity. Determine(?) TB-LAM (Alere, MA, USA) had highest sensitivity at low CD4 cell counts: 66.7, 51.7 and 39.0% at <50 cells, <100 cells and <200 cells per μl, respectively; specificity was greater than 98% for all strata. There was an incremental sensitivity when Determine TB-LAM was combined with smear microscopy, which did not differ statistically from the sensitivities obtained by testing a single sputum sample with the Xpert(?) MTB/RIF (Cepheid; CA, USA) assay. Determine TB-LAM is a simple, low-cost alternative to existing diagnostic assays for TB screening in HIV-infected patients with very low CD4(+) cell counts.     

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.     

A novel method of sputum processing for cytologic diagnosis of lung cancer

OBJECTIVE: To compare the diagnostic sensitivity and cytologic findings of the sputum-processing method with those of the traditional sputum smear method. STUDY DESIGN: From May to December 2001, 300 consecutive sputum samples were collected from 168 patients suspected of having lung cancer in the Chest Department, Taipei Veterans General Hospital. After the sputum smear method, the remaining sputum material was processed by homogenization, filtration and fixation. All the slides were stained with Papanicolaou stain and reviewed by 2 cytologists. RESULTS: Of the 300 sputum samples, 141 from 79 patients were finally diagnosed as lung malignancies. The mean number of sputum samples was 1.78 per patient. Among the 79 patients, 46 had peripheral lung malignancies (58.2%). The overall diagnostic sensitivities of sputum smear and sputum-processing methods were 29% and 31%, respectively (P = .776). Tumor location and cell types did not change the difference significantly; however, among patients with small cell lung cancer, there was a higher detection rate with the sputum-processing method (50% vs. 20%, P = .350). Eight patients with negative results with the sputum smear had positive results with the sputum-processing method (8 of 79 = 10.1%). Microscopic morphologic differences between the 2 methods were described. CONCLUSION: There was no significant difference in diagnostic sensitivity between the sputum smear and sputum-processing methods. However, the sputum-processing method may play a role in patients with small cell lung carcinoma.     

Culture Conversion Rate at 2 Months of Treatment According to Diagnostic Methods among Patients with Culture-Positive Pulmonary Tuberculosis

Introduction

The culture-negative conversion rate of sputum after 2 months of treatment in patients with pulmonary tuberculosis (TB) is used as a reliable surrogate marker for relapse after completion of treatment. We hypothesized that culture conversion of sputum at 2 months of anti-TB treatment and the time to culture conversion are different among pulmonary TB patients who are diagnosed using different methods.

Methods

Culture-confirmed pulmonary TB patients who were diagnosed between 1 January, 2011 and 31 December, 2012 were classified into three groups based on the diagnostic method that prompted treatment initiation: positive acid-fast bacilli (AFB) staining of sputum (smear-positive group), negative AFB staining, but Mycobacterium tuberculosis was cultured from sputum (culture-positive group), and positive AFB staining, positive polymerase chain reaction (PCR) for M. tuberculosis, or culture of M. tuberculosis from a bronchoscopic specimen (bronchoscopy group). Rates of negative mycobacterial culture conversion at 2 months of anti-TB treatment and the time to negative culture conversion of sputum were compared among the three groups.

Results

A total of 203 patients with culture-confirmed pulmonary TB were included in the final analysis. TB patients in the culture-positive group (94.1%) and the bronchoscopy group (97.6%) showed a higher culture conversion rate at 2 months of treatment than those in the smear-positive group (78.7%, P = 0.001). Additionally, the time to culture conversion was longer in the smear-positive group (median, 40 days) than in the culture-positive (median, 19 days; P = 0.009) and bronchoscopy groups (median, 29 days; P = 0.004).

Conclusions

The higher culture conversion rate at 2 months and the shorter time to culture conversion among pulmonary TB patients with a negative AFB smear suggests the feasibility of shortening treatment duration and isolation in these patients.     

Cost Analysis of a Nucleic Acid Amplification Test in the Diagnosis of Pulmonary Tuberculosis at an Urban Hospital with a High Prevalence of TB/HIV

Introduction

The Centers for Disease Control and Prevention has recommended using a nucleic acid amplification test (NAAT) for diagnosing pulmonary tuberculosis (TB) but there is a lack of data on NAAT cost-effectiveness.

Methods

We conducted a prospective cohort study that included all patients with an AFB smear-positive respiratory specimen at Grady Memorial Hospital in Atlanta, GA, USA between January 2002 and June 2008. We determined the sensitivity, specificity, and positive and negative predictive value of a commercially available and FDA-approved NAAT (amplified MTD, Gen-Probe) compared to the gold standard of culture. A cost analysis was performed and included costs related to laboratory tests, hospital charges, anti-TB medications, and contact investigations. Average cost per patient was calculated under two conditions: (1) using a NAAT on all AFB smear-postive respiratory specimens and (2) not using a NAAT. One-way sensitivity analyses were conducted to determine sensitivity of cost difference to reasonable ranges of model inputs.

Results

During a 6 1/2 year study period, there were 1,009 patients with an AFB smear-positive respiratory specimen at our public urban hospital. We found the NAAT to be highly sensitive (99.6%) and specific (99.1%) on AFB smear-positive specimens compared to culture. Overall, the positive predictive value (PPV) of an AFB smear-positive respiratory specimen for culture-confirmed TB was 27%. The PPV of an AFB smear-positive respiratory specimen for culture-confirmed TB was significantly higher for HIV-uninfected persons compared to those who were HIV-seropositive (152/271 [56%] vs. 85/445 [19%]; RR = 2.94, 95% CI 2.36–3.65, p<0.001). The cost savings of using the NAAT was $2,003 per AFB smear-positive case.

Conclusions

Routine use of the NAAT on AFB smear-positive respiratory specimens was highly cost-saving in our setting at a U.S. urban public hospital with a high prevalence of TB and HIV because of the low PPV of an AFB smear for culture-confirmed TB.     

The Quality of Sputum Smear Microscopy in Public-Private Mix Directly Observed Treatment Laboratories in West Amhara Region,Ethiopia

Ethiopia adopted Public-Private Mix Directly Observed Treatment Short Course Chemotherapy (PPM-DOTS) strategy for tuberculosis (TB) control program. Quality of sputum smear microscopy has paramount importance for tuberculosis control program in resource-poor countries like Ethiopia. A cross-sectional study was conducted to assess the quality of sputum smear microscopy in 37 Public-Private Mix laboratories in West Amhara, Ethiopia. The three external quality assessment methods (onsite evaluation, panel testing and blind rechecking) were employed. Onsite assessment revealed that 67.6% of PPM-DOTS laboratories were below the standard physical space (5 X 6) m². The average monthly workload per laboratory technician was 19.5 (SD±2.9) slides with 12.8% positivity rate. The quality of Acid Fast Bacilli (AFB) staining reagents was sub-standard. The overall agreement for blind rechecking of 1,123 AFB slides was 99.4% (Kappa = 0.97). Reading of 370 AFB panel slides showed 3.5% false reading (Kappa = 0.92). Moreover, the consistency of reading scanty bacilli slides was lower (93%) compared to 1+, 2+ and 3+ bacilli. Based on blind rechecking and panel testing results, PPM-DOTS site laboratories showed good agreement with the reference laboratory. Physical space and qualities of AFB reagents would be areas of intervention to sustain the quality of sputum smear microscopy. Therefore, regular external quality assessment and provision of basic laboratory supplies for TB diagnosis would be the way forward to improve the quality of sputum smear microscopy services in PPM-DOTS laboratories.     

Diagnostic accuracy of fine needle aspiration cytology of the thyroid: impact of ultrasonography and ultrasonographically guided aspiration

OBJECTIVE: To determine the impact of ultrasonography on the diagnostic accuracy of fine needle aspiration cytology (FNAC) of the thyroid. STUDY DESIGN: We compared two FNAC series. In period 1 we used neither ultrasonograph nor ultrasonographically-guided FNAC in the evaluation of thyroid nodules, while both tools were routinely applied in period 2. Moreover, in the former period all cellular follicular lesions were encountered among suspicious findings, while in period 2 we advised regular follow-up examinations instead of immediate surgery for patients with no significant atypia. The basis of follow-up examinations was ultrasonographic volumetry of the nodule and repeat FNAC on growing nodules. RESULTS: The number of FNAC, positive predictive value of FNAC, number of malignancies, sensitivity, the specificity and diagnostic accuracy were higher in period 2 as compared with period 1: 3,446 vs. 1,448; 45% vs. 16%, 39 vs. 29, 92% vs. 76%, 65% vs. 87% and 66% vs. 87%, respectively. CONCLUSION: The introduction of ultrasonography permits higher diagnostic accuracy of the evaluation process. This is achieved not only by lessening false negative reports but, more important, by decreasing false positive results.     

Diagnosis of Tuberculosis by Using a Nucleic Acid Amplification Test in an Urban Population with High HIV Prevalence in the United States

Background

Use of nucleic acid amplification tests (NAAT) for the diagnosis of Mycobacterium tuberculosis (TB) has been recommended on respiratory specimens submitted for acid-fast bacilli (AFB) testing. It also helps distinguish between TB and non-tuberculous mycobacteria (NTM) species in a setting where NTM rates are relatively high. The purposes of this study are to describe the trend and characteristics of all AFB smear-positive respiratory samples that underwent amplified Mycobacterium tuberculosis direct (MTD) testing, a type of NAAT, and to evaluate the clinical utility and necessity of the test for diagnosis of TB in a population with high-HIV prevalence.

Methods

Prospective diagnostic testing and retrospective data analyses were conducted on all AFB smear-positive respiratory samples that underwent MTD testing from 2001 to 2011 at Grady Memorial Hospital (GMH), Atlanta, USA. The test performance was compared to culture.

Results

A total of 2,240 AFB smear-positive specimens from 1,412 patients were tested and analyzed in the study. The proportion of specimens that were culture-positive for TB was 28.5%. Sensitivity, specificity, positive predictive value, and negative predictive value of the MTD were 99.0%, 98.0%, 95.3% and 99.6%, respectively. A downward trend was observed in the yearly numbers as well as the proportions of MTD-positive specimens during the study period (p<0.01). There were 2,027 (90.5%) specimens from patients with known HIV status, of which 70.6% was HIV positive and the majority of them (81.8%) had CD4 counts of less than 200 cells/µL. HIV-positives were more likely to have NTM compared to HIV negatives (67.7% vs. 35.4%, p<0.01).

Conclusion

Despite the decrease in the incidence of TB, NAAT continues to be an accurate and important diagnostic test in a population with high HIV prevalence, and it differentiates TB and NTM organisms.     

Yield of Two Consecutive Sputum Specimens for the Effective Diagnosis of Pulmonary Tuberculosis

Background

From long instances, it is debatable whether three sputum specimens are required for the diagnosis of pulmonary tuberculosis (TB) or TB can be diagnosed effectively using two consecutive sputum specimens. This study was set out to evaluate the significance of examining multiple sputum specimens in diagnosis of TB.

Methods

We retrospectively reviewed the acid-fast bacillus (AFB) smear and culture results of three consecutive days’ sputum specimens from 413 confirmed TB patients which were detected as part of a larger active case finding study in Dhaka Central Jail, the largest correctional facility in Bangladesh.

Results

AFB was detected from 81% (n = 334) patients, of which 89% (n = 297) were diagnosed from the first and additional 9% (n = 30) were from the second sputum specimen. M. tuberculosis growth was observed for 406 patients and 85% (n = 343) were obtained from the first sputum and additional 10% (n = 42) were from the second one. The third specimen didn’t show significant additional diagnostic value for the detection of AFB by microscopy or growth of the M. tuberculosis.

Conclusions

We concluded from our study results that examining two consecutive sputum specimens is sufficient enough for the effective diagnosis of TB. It can also decrease the laboratory workload and hence improve the quality of work in settings with high TB burden like Bangladesh.     

LED-Fluorescence Microscopy for Diagnosis of Pulmonary Tuberculosis under Programmatic Conditions in India

Background

Light-emitting diode fluorescence microscopy (LED-FM) has been shown to be more sensitive than conventional bright field microscopy using Ziehl-Neelsen (ZN) stain in detecting sputum smear positive tuberculosis in controlled laboratory conditions. In 2012, Auramine O staining based LED-FM replaced conventional ZN microscopy in 200 designated microscopy centres (DMC) of medical colleges operating in collaboration with India’s Revised National Tuberculosis Control Programme. We aimed to assess the impact of introduction of LED-FM services on sputum smear positive case detection under program conditions.

Methods

This was a before and after comparison study. In 15 randomly selected medical college DMCs, all presumptive TB patients who underwent sputum smear examination in the years 2011 (before LED-FM) and 2012 (after LED-FM) were compared. An additional 15 comparable DMCs that implemented conventional ZN sputum smear microscopy were also selected for comparison between 2011 and 2012.

Results

The proportion of presumptive TB patients (PTP)found sputum smear positive increased by 30%- from 13.6% (3432/25159) in 2011 to 17.8% (4706/26426) in 2012 (P value <0.01) in the sites that implemented LED-FM microscopy, whereas in DMCs where the ZN staining procedure is followed the proportion of sputum smear positive had remained unchanged (13.0%versus 12.6%;P value0.31).

Conclusion

Use of LED-FM significantly increased the proportion of smear positive cases among presumptive TB patients under routine program conditions in high workload laboratories. The study provides operational evidence needed to scale-up the use of LED-FM in similar settings in India and beyond.     

Tuberculosis Laboratory Diagnosis Quality Assurance among Public Health Facilities in West Amhara Region,Ethiopia

Introduction

Reliable smear microscopy is an important component of Directly Observed Treatment Scheme (DOTS) strategy for TB control program in countries with limited resources. Despite external quality assessment is established in Ethiopia, there is lower TB detection rate (48%) in Amhara region compared to the World Health Organization (WHO) estimate (70%). This highlights the quality of smear microscopy needs to be evaluated. Therefore, the aim of this study was to assess the quality of sputum smear microscopy performance among health center laboratories in West Amhara region, Ethiopia.

Materials and Methods

A cross sectional study was conducted from July 08, 2013 to July 07, 2014. Data were collected from 201 public health center laboratories using a structured questionnaire. Slides were collected based on Lot Quality Assurance Sampling (LQAS) method and rechecked blindly by trained laboratory technologists. The data were entered into EPI info V.7 and smear quality indicators and AFB results were analyzed by SPSS version 20.

Results

Among 201 laboratories enrolled in this study, 47 (23.4%) laboratories had major errors. Forty one (20.4%) laboratories had a total of 67 false negative and 29 (14.4%) laboratories had a total of 68 false positive results. Specimen quality, smear thickness and evenness were found poor in 134 (66.7%), 133 (66.2%) and 126 (62.7%) laboratories, respectively. Unavailability of microscope lens cleaning solution (AOR: 2.90; 95% CI: 1.25–6.75; P: 0.013) and dirty smears (AOR: 2.65; 95% CI: 1.14–6.18; P: 0.024) were correlated with false negative results whereas no previous EQA participation (AOR: 3.43; 95% CI: 1. 39-8.45; P: 0.007) was associated with false positive results.

Conclusion

The performance of health facilities for sputum smear microscopy was relatively poor in West Amhara region. Hence, strengthening the EQA program and technical support on sputum smear microscopy are recommended to ensure quality tuberculosis diagnostic service.     

Fuchsin fluorescence in Mycobacterium tuberculosis: the Ziehl-Neelsen stain in a new light

Tuberculosis (TB) is often diagnosed by observation of reddish pink fuchsin-stained Mycobacterium tuberculosis (MTB) in Ziehl-Neelsen (Z-N) stained smears by transmitted light microscopy. MTB too faintly stained with fuchsin to be seen by transmitted light may be detected by their green-excited orange-red fluorescence; this finding may be clinically relevant.     

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.