Surveillance of Acute Respiratory Infections in Mumbai during 2011-12.

Purpose: Acute respiratory infections (ARIs) are a leading cause of morbidity and mortality in individuals aged less than 5 years. ARI often leads to hospitalisation, and it has been indicated that causative viral and bacterial infections go undetermined and results in the occurrence of resistant strains. The objective of the study was to assess the prevalence of various viral and bacterial infections in patients with ARIs. Materials and Methods: Two hundred samples were collected from July 2011 to July 2012 with patients suffering from ARI. Viral and bacterial infections were determined by real time reverse transcriptase polymerase chain reaction. Results: Infl uenza-like illness (ILI) consisted of 109 patients and ARI consisted of 91 patients. Pandemic infl uenza A H1N1 was the major viral infection with 21 (19.2%) patients in ILI as compared with 16 (17.4%) patients in ARI. Respiratory syncytial virus (RSV) was found to be 1 (0.9%) in ILI and ARI. Viral co-infections were 16 (14.4%) in ILI and 4 (4.37%) in ARI where pandemic infl uenza A H1N1 and infl uenza type B were major contributors. In bacterial infections, Streptococcus pneumoniae with 11 (10.9%) cases were predominant in both the groups. Bacterial co-infection accounted for only 1 (1.09%) case in both the groups but the most signifi cant fi nding was the viral-bacterial co-infection in which Haemophilus infl uenzae was the major co-infecting bacteria with the infl uenza viruses with 4 (4.36%) cases as compared with Streptotoccus pneumoniae. Conclusion: This data indicate the need to undertake continued surveillance that will help to better defi ne the circulation of respiratory viruses along with the bacterial infections.

Utility of in vitro proton magnetic resonance spectroscopy in aetiological characterisation of brain abscesses.

Purpose: Brain abscesses often present an aetiological dilemma. Microscopy is insensitive and culture techniques are time consuming. Hence, a new rapid technique in vitro Proton Magnetic Resonance Spectroscopy ( 1 HMRS) was evaluated for its usefulness in the identification of aetiology of brain abscesses. Materials and Methods: A total of 39 pus specimens from brain abscesses were subjected to in vitro 1 HMRS. These pus specimens were also processed by conventional culture methods. The spectral patterns generated by in vitro 1 HMRS were further correlated with culture results. Results: Pus specimens which showed the presence of anaerobes on culture revealed the presence of multiplet at 0.9 ppm (100%), lactate-lipid at 1.3 ppm (100%), acetate at 1.92 ppm (100%) and succinate at 2.4 ppm (75%). Pus specimens that revealed the presence of facultative anaerobes on culture showed a pattern B, i.e., the presence of lactate-lipid at 1.3 ppm (100%), acetate at 1.92 ppm (88.88%) along with the multiplet at 0.9 ppm (100%). Pattern C was seen in aerobic infection which showed the presence of lactate-lipid at 1.3 ppm (100%) along with the multiplet at 0.9 ppm. Pus from two tuberculous abscesses showed the complete absence of multiplet at 0.9 ppm. Conclusions: We observed in this study that it was possible to differentiate bacterial and tuberculous brain abscesses using in vitro 1 HMRS. Further, it was also possible to distinguish between aerobic and anaerobic brain abscesses on the basis of spectral patterns. In vitro 1 HMRS of fungal and actinomycotic brain abscess are also presented for its unusual spectra.

Rapid identification of non-sporing anaerobes using nuclear magnetic resonance spectroscopy and an identification strategy.

PURPOSE: The non-sporing anaerobes cause a wide spectrum of infections. They are difficult to culture and their identification is tedious and time-consuming. Rapid identification of anaerobes is highly desirable. Towards this end, the potential of nuclear magnetic resonance (NMR) spectroscopy for providing a fingerprint within the proton spectrum of six genera belonging to anaerobes reflecting their characteristic metabolites has been investigated. METHODS: NMR analysis was carried out using Mercury plus Varian 300 MHz (7.05 T) NMR spectrophotometer on six different anaerobes. These included Bacteroides fragilis, Prevotella melaninogenica, Prevotella denticola, Fusobacterium necrophorum, Peptococcus niger and Peptostreptococcus spp. After the NMR analysis (256/512 scans), the different peaks were noted. The eight pus specimens, which yielded pure culture of anaerobe, also were analysed similarly. RESULTS: The major resonances of multiplex of amino acids/lipid at 0.9 ppm along with lactate/lipid at 1.3 ppm, acetate at 1.92 ppm and multiplex of lysine at 3.0 ppm remained constant to label the organism as an anaerobe. There was a difference found in the MR spectra of different genera and species. A simple algorithm was developed for the identification of the six different anaerobes studied. The MR spectra of the pure culture of the organism matched the MR spectra of pus from which the organism was isolated. CONCLUSIONS: MR-based identification was of value in the identification of anaerobes. However, a larger database of the peaks produced by anaerobes needs to be created for identification of all genera and species. It could then have the potential of diagnosing an anaerobic infection in vivo and thus expedite management of deep-seated abscesses.

Parasitic diarrhoea in patients with AIDS.

BACKGROUND: Diarrhoea is a common clinical manifestation of HIV infection regardless of whether or not patients have AIDS. Two newly recognized opportunistic coccidial protozoa are parasitic pathogens in AIDS patients. We attempted to determine the common parasites in Indian patients with AIDS. METHODS: Between October 1994 and December 1996, a total of 110 stool specimens from 94 AIDS patients with acute or chronic diarrhoea were examined by microscopy of wet mounts and smears stained by a modified Ziehl-Neelsen's (cold) staining method. RESULTS: Isospora belli was the most frequently encountered parasite in 17% of patients, followed by Entamoeba histolytica in 14.9% and Cryptosporidium in 8.5%. Strongyloides stercoralis and Giardia lamblia were detected in 5.3% and 4.3% of patients, respectively. CONCLUSION: The presence of different parasites in 56.4% of stool specimens of patients with AIDS indicates that their specific diagnosis is essential. This will help initiate therapy to reduce the morbidity and mortality among such patients due to these pathogens.