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Background & objectives: Scrub typhus or chigger borne typhus, caused by Orientia tsutsugamushi is an emerging vector-borne disease as large numbers of cases have been reported in various tropical countries. It is transmitted to humans through bites of infected chiggers (larval mites). The knowledge about the vector, its distribution, density and habitat are important so as to understand the epidemiology of scrub typhus in a given area. To control rickettsial infections, regular rodent-vector surveillance should be planned in areas where the disease transmission is occurring and it will also help to strengthen the existing entomological data related to the vector of scrub typhus in northern India. Methods: In the present study, rodent-vector surveillance was planned for one whole year, covering both mite active and non-active seasons (October 2019–December 2020) in selected areas of Chandigarh and Punjab in north India. Rodent tissues and mites were also examined for the presence of O. tsutsugamushi by nested PCR for 56 kDa gene and real-time PCR for 47 kDa outer membrane protein gene. 18S gene PCR was performed for molecular identification of mites. Results: In the surveillance, three types of ectoparasite, viz. mites, fleas and ticks were obtained in rodents. All mites found were of Laelapidae family. None of the pooled rodent tissue samples as well as mite samples were found positive for O. tsutsugamushi by nested PCR for rickettsial DNA. Interpretation & conclusion: In the present study, we did not get any evidence of carriage of O. tsutsugamushi in either mites or rodents collected and sampled in selected regions in Chandigarh and Punjab. We need to strengthen the entomological surveillance over a broader region and increase the frequency of trapping rodents to increase clarity on vector-reservoir dynamics in this geographical region.
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Purpose: To report clinical features, antibiotic susceptibility profile, management, and outcomes of a cluster outbreak of post?cataract surgery Pseudomonas stutzeri endophthalmitis. Methods: This was a hospital?based case series in which 14 patients with acute postoperative endophthalmitis who underwent cataract surgery on the same day were included. Based on severity of presentation, they either underwent pars plana vitrectomy (PPV) with intraocular antibiotics (IOAB) or vitreous tap with IOAB. Vitreous aspirates and environmental surveillance samples were inoculated on culture media and further processed by MALDI?TOF MS for identification and Vitek3 for susceptibility profile. Results: There were 8 females and 6 males with a mean age of 62.14 ± 8.08 years. Presenting signs included corneal folds (100%), hypopyon (57.1%) and fibrin (50%). Ten patients with mild presentation underwent vitreous tap with IOAB. Four patients with severe presentation underwent PPV with IOAB. Pseudomonas stutzeri was isolated from the vitreous samples and was pan?sensitive. Six eyes required multiple interventions. Favorable outcome was obtained in 12 eyes, one eye developed phthisis, and one patient was lost to follow?up. Conclusion: We report the first ever cluster outbreak of Pseudomonas stutzeri endophthalmitis following phacoemulsification with IOL implantation in a single surgeon setting. Majority of the patients had a mild presentation and responded well to targeted anti?microbial treatment.
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ABSTRACT Rickettsial diseases (RD) are a group of endotheliotropic infectious diseases caused by different species of genera Rickettsia. RD are not an uncommon disease and may be misdiagnosed during the evaluation of acute febrile illness due to a lack of reliable serological marker and diagnostic culture methods. Clinical manifestation of RD varies from febrile illness with rashes and myalgia to fatal complications such as shock and respiratory failure. We describe a case of a young male who presented initially with acute febrile illness, followed by shock and respiratory failure, and unfortunately succumbed to death. A post-mortem examination showed histological features of endotheliotropic infection, such as interstitial / perivascular edema in various organs and noncardiogenic pulmonary edema (suggesting increased vascular permeability) and evidence of vasculitis in the lung, liver, and intestines. Molecular studies performed from lung, liver, and kidney tissue confirm the diagnosis of spotted fever group rickettsial disease due to Rickettsia conorii.
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Background: Urine culture is a gold standard in the diagnosis of urinary tract infection. Clean catch midstream urine collection and prompt transportation is essential for appropriate diagnosis. Improper collection and delay in transportation leads to diagnostic dilemma. In developing countries, higher ambient temperatures further complicate the scenario. Here, we have evaluated the role of boric acid as a preservative for urine samples prior to culture in female patients attending outpatient department at our center. Materials and Method: Consecutive 104 urine samples were cultured simultaneously in plain uricol (Control-C) and boric acid containing tubes from Becton Dickinson urine culture kit (Boric acid group-BA). Results: In the real-time evaluation, we found that in almost 57% (59/104) of the urine samples tested, it was more effective in maintaining the number of the organisms as compared to samples in the container without any preservative. Our in vitro study of simulated urine cultures revealed that urine samples could be kept up to 12 h before culture in the preservative without any inhibitory effect of boric acid. Though the use of boric acid kit may marginally increase the initial cost but has indirect effects like preventing delays in treatment and avoidance of false prescription of antibiotics. If the man-hours spent on repeat investigations are also taken into consideration, then the economic cost borne by the laboratory would also decrease manifold with the use of these containers.
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Background & objectives: Traditionally, rabies diagnosis is made by demonstration of rabies viral antigen by direct immunofluorescence (DIF) and mouse inoculation test (MIT). The present study was carried out to evaluate the role of reverse transcriptase-polymerase chain reaction (RT-PCR) in comparison with these conventional techniques for the diagnosis of rabies. Methods: Skin biopsies, corneal impression smears and saliva sample were collected ante-mortem and brain tissue and CSF were collected post-mortem from ten clinically suspected rabies patients. DIF, Seller staining, MIT and RT-PCR were performed on the patients’ samples for the diagnosis of rabies. The ability of RT-PCR to detect rabies virus earlier as compared to other assays was tested both for reference virus as well as clinical isolates. Results: All samples taken ante-mortem were negative for DIF test. Six of 10 post-mortem brain tissues of the clinically suspected patients were positive both by RT-PCR and MIT, of these six, five were positive by DIF test and four were positive by Seller stain. RT-PCR could detect the rabies virus earlier as compared to DIF, both from clinical isolates and fixed rabies virus. Interpretation & conclusions: The present results showed 100 per cent sensitivity and specificity of RT-PCR as compared to 83.3 per cent of DIF and 66.7 per cent of Sellers stain for diagnosis of rabies. RT-PCR also detected rabies viral infection earlier as compared to conventional tests and can also be used on ante-mortem samples. Thus, the present study shows the usefulness of RT-PCR as an alternative to MIT for the confirmation of rabies diagnosis.
Subject(s)
Autopsy/methods , Humans , Reverse Transcriptase Polymerase Chain Reaction/methods , Rabies/diagnosis , Adult , Biopsy , Skin/pathology , Saliva , DiagnosisABSTRACT
The study evaluated drinking water from localities in and around Chandigarh for fecal coliforms, V.cholerae and Enterotoxigenic E.coli and correlate with occurrence of acute gastroenteritis occurring from the same region. Drinking water sample were collected from various sources from the defined area. Samples were tested for fecal coliforms and E.coli count by multiple tube method and pathogens by membrane filtration technique. E. coli were screened for heat labile toxin (LT) by the reverse passive agglutination method and heat stable toxin (ST) by ELISA. Stool samples from cases of acute gastroenteritis from the same region and time were collected and processed for V. cholerae, Enterotoxigenic E coli (ETEC) and others like Salmonella, Shigella and Aeromonas spp. Of 364 water samples examined, 116 (31.8%) samples were contaminated with fecal coliforms (58.5% rural, 33.4% semi-urban and 11.1% from urban areas). E. coli were grown from 58 samples. Ninety-two isolates of E. coli were tested for enterotoxins of which 8 and 24 were positive for LT and ST respectively. V. cholerae were isolated from 2 samples during the outbreak investigation. Stored water samples showed a significantly higher level of contamination and most of Enterotoxigenic E. coli were isolated from stored water samples. A total of 780 acute gastroenteritis cases occurred; 445 from semiurban, 265 rural and 70 from urban areas. Out of 189 stool samples submitted, ETEC were the commonest (30%) followed by V. cholerae (19%), Shigellae (8.4%), Salmonellae (2.1%) and Aeromonas (2.6%). ST-ETEC (40/57) were commoner than LT- ETEC(17/57). In the present study, high levels of contamination of drinking water supplies (32.1%) correlated well with cases of acute gastroenteritis. Majority of cases of acute gastroenteritis occurred in the semi-urban area corresponding with high level of contamination (33.4%). The highest level of water contamination was seen in rural areas (58.5%) but the number of acute gastroenteritis cases were lesser (33.9%) as ponds were infrequently used for drinking purpose. Safer household water storage and treatment is recommended to prevent acute gastroenteritis, together with point-of-use water quality monitoring.