Pulmonary cryptosporidiosis in a case of adenocarcinoma of stomach: A rare case report.

Cryptosporidium species are commonly known to cause chronic intractable diarrhea in patients suffering from human immunodeficiency virus (HIV)-acquired immunodeficiency syndrome, however extra-intestinal presentations have been rarely reported. Hereby, we report a rare case of isolated pulmonary cryptosporidiosis in a 75-year-old HIV-negative patient with metastatic carcinoma of the stomach who was managed conservatively with hemostatic radiotherapy for palliative care. The patient had presented with cough with expectoration for 2 months. Sputum microscopic examination was suggestive of pulmonary cryptosporidiosis. There was no evidence of intestinal cryptosporidiosis. Therapy for pulmonary cryptosporidiosis was started with tablet nitazoxanide. The patient succumbed to the disease few days later following discharge. Although rare, patients with disseminated gastrointestinal malignancy can potentially have isolated pulmonary cryptosporidiosis.

Evaluation of real time polymerase chain reaction targeting mpb64 gene for diagnosis of extrapulmonary tuberculosis.

BACKGROUND: Paucibacillary nature of extrapulmonary tuberculosis (EPTB) has paved way for molecular methods increasingly being used for diagnosis. We undertook a study for evaluation of sensitivity and specificity of real-time polymerase chain reaction (RT-PCR) targeting mpb64 gene for diagnosis of EPTB. METHODS: A total of 152 clinical samples from suspected cases of EPTB were included in this study. All samples were extracted using spin column based commercial DNA extraction kit and were subjected to RT-PCR targeting mpb64 and IS6110. Smear and culture was also done for samples whenever quantity was sufficient. Cytology report was noted from hospital information system. Receiver operating characteristic (ROC) curve analysis was done for determining cut-off Ct value for mpb64 RT-PCR. Melt curve analysis was done for samples whose cycle threshold (Ct) value was more than 37. The sensitivity and specificity of the mpb64 RT-PCR was calculated using a composite gold standard i.e., positive for one or more of the following: microscopy (including fine needle aspiration cytology (FNAC), acid-fast bacilli positivity), culture and IS6110 RT-PCR. RESULTS: Out of the 152 samples, 72 (47.4%) were positive for tuberculosis by composite gold standard. Samples consisted of ascitic fluid (12), CSF (35), pus (23), lymph node aspirate (35), pleural fluid (37), synovial fluid (4), urine (1), pericardial fluid (1) and tissue bits (4). Microscopy (AFB smear including lymph node aspirate) was done for 124 samples of which 43 (34.7%) were positive. Culture results were available for 79 samples, 25 (31.6%) of which were positive and 42 (27.6%) of the 152 samples were positive by IS6110 PCR. Based on ROC and melt curve analysis, mpb64 RT-PCR was able to detect 38 (52.8%) of the 72 positive samples. In comparison to IS6110 RT PCR, 4 additional cases were detected by mpb64 RT-PCR. Compared to composite gold standard mpb64 showed overall sensitivity of 52.8%. CONCLUSION: The mpb64 RT-PCR is highly specific or MTB and can be used as a supplemental test for diagnosis of EPTB along with other diagnostic tests. However the overall sensitivity of mpb64 RT-PCR is too low to be used as an independent test for diagnosis of EPTB. Combining the results of IS6110 RT PCR and mpb64 RT PCR improved the overall sensitivity and hence mpb64 can be used as an additional target for diagnosis of EPTB.

Synthesis and in vitro antitubercular activity of pyridine analouges against the resistant Mycobacterium tuberculosis.

Mycobacterium tuberculosis (MTB) infection has become a growing health risk as multi-drug resistant strain (MDR-MTB) has emerged worldwide. The development of isoniazid (INH)-resistant M. tuberculosis strains dictate the need to re-design this old drug to create effective analogs against the resistant INH strains. Synthesis and the biological activity of isoniazid and pyridine derivatives were successfully carried out with elaborated characterization by spectral data. Amongst the synthesized compounds; 1 and 2 displayed encouraging antimycobacterial activity with IC50 of 3.2 µM and 1.5 µM against the H37Rv strain. The MIC of test compounds 1 and 2 were also assessed against the 5 drug resistant isolates (FQ-R1, INH-R1, INH-R2, RIF-R1 and RIF-R2) of MTB strains under aerobic conditions and compound 1 [MIC = 3.2 µM for FQ-R1; MIC = 140 µM for INH-R1; MIC = 160 µM for INH-R2; MIC = 2.4 µM towards RIF-R1; MIC = 4.2 µM for RIF-R2] and 2 [MIC = 3.3 µM for FQ-R1; MIC = 170 µM for INH-R1; MIC = 190 µM for INH-R2; MIC = 1.8 µM for RIF-R1; MIC = 8.4 µM for RIF-R2] have shown significant activity at non-cytotoxic concentration in comparison to the standard drug.

Evaluation of performance of direct disk diffusion test from positively flagged blood culture broth: A large scale study from South India.

BACKGROUND: Rapid turnaround time of blood culture reports should be the main motive for a clinical microbiologist for optimal patient care. Categorical agreement (CA) between direct disk diffusion (dDD) and reference disk diffusion (rDD) may vary between laboratories. AIMS AND OBJECTIVES: This study was designed to determine the CA and understand various types of errors associated with antibiotic organism combination, so that caution can be derived while interpreting and reporting dDD results in the earliest meaningful time frame. MATERIALS AND METHODS: In the present study, dDD results were compared to the rDD results from the positive blood culture bottles. CA and various types of errors were evaluated. RESULTS: A total of 965 pathogens and 7106 organism antibiotic combinations were evaluated in this study. Overall, there was a CA of 96% which was extremely satisfactory. The categorical disagreement was found only in 4% of organism antibiotic combinations; majority of which were major error (ME, 2.1%) followed by very ME (1%) and minor error (0.9%). The errors were marginally high for Enterobacteriaceae testing against ß lactam- ß lactamase inhibitor combinations, for Pseudomonas species against aminoglycosides and ciprofloxacin and Staphylococcus species against cefoxitin, one should be vigilant while reporting dDD result of these antibiotic organism combinations. CONCLUSION: dDD is of paramount importance for early institution of targeted therapy and is considered as one of the key stewardship intervention. Our study gives an insight that every laboratory must perform dDD for positively flagged blood culture specimens; the result of which should be confirmed later by performing rDD. One should be vigilant while reporting dDD result of BL BLI for Enterobacteriaceae; aminoglycosides and CF for Pseudomonas species; cefoxitin for Staphylococcus species and HLG for Enterococcus species. Supplementary tests such as MRSA latex should be included when necessary.

Pyridines: Multidrug-resistant tuberculosis (MDR-TB) inhibitors.

Mycobacterium tuberculosis (MTB) infection has become an increasing health threat due to the worldwide emergence of multidrug-resistant MTB (MDR-MTB) strain. Isoniazid (pyridine) resistance problem is a complex process and is associated with mutations in several genes. However, the emergence of isoniazid (INH) resistant M. tuberculosis strains dictates the necessity for redesigning this old drug in order to create analogs effective against INH-resistant strains by using rational approach. In light of these findings, the present review discusses the synthesis, structural optimization, and modification in pyridine structure to combat the problem of multidrug-resistant tuberculosis.

Mycobacterium Tuberculosis (MTB) GyrB inhibitors: An attractive approach for developing novel drugs against TB.

New classes of drugs are needed to treat tuberculosis (TB) in order to combat the emergence of resistance (MDR and XDR) to existing agents and shorten the duration of therapy. Mycobacterial DNA gyrase B subunit has been identified to be one of the potentially under exploited drug targets in the field of antitubercular drug discovery. In the present review, we discussed the synthesis, structural optimization and docking study of effective potent DNA gyrase inhibitor against M. tuberculosis, with improved properties such as enhanced activity against MDR strains, reduced toxicity. Based on this progress, if we can successfully leverage the opportunities in this target, there is hope that we will be able to raise novel gyrase inhibitor in earnest in the long.