Evaluation of a commercial Dengue NS1 enzyme-linked immunosorbent assay for early diagnosis of dengue infection.

Purpose: Dengue is one of the most serious mosquito-borne viral infections affecting tropical and subtropical countries in the world. Since there is no immunoprophylactic or specific antiviral therapy available, timely and rapid diagnosis plays a vital role in patient management and implementation of control measures. This paper evaluates a commercially available NS1 antigen capture ELISA vis-a-vis SD bioline Dengue NS1 antigen test for early detection of dengue virus. Materials and Methods: To evaluate a commercial NS1 antigen detection kit vis-a-vis SD bioline Dengue NS1 antigen test, a total of 91 clinical samples were tested. Virological investigations with regard to dengue virus, viz. NS1 antigen capture ELISA (Panbio, Australia), SD bioline Dengue NS1 antigen test, RT-PCR and virus isolation were performed. Results: Out of 91 samples, 24 (26%) were positive by NS1 antigen capture ELISA, 15 (16%) by SD bioline Dengue NS1 antigen test and 11(12%) positive by RT-PCR analysis. The RT-PCR-positive samples were further subjected to virus isolation and resulted in three isolates. The results of the Panbio NS1 antigen capture ELISA, SD bioline Dengue NS1 antigen test, RT-PCR and virus isolation were correlated among themselves. Conclusions: The present study comprehensively established the utility of NS1 antigen ELISA in early diagnosis of dengue infection.

Work zone noise levels at Aarti steel plant, Orissa and its attenuation in far field.

The outdoor noise levels from the various work places of the integrated steel plant were measured. The average noise level (Leqst) at the outdoor was found between 59-84 dBA. The combined noise level (Leq) of the plant was 90 dBA and 92 dBA on 1.12.2006 and 16.12.2006, respectively. The noise levels in the far fields were found between 43-70 dBA for daytime and meet the noise quality for industrial (75 dBA) area and residential (55 dBA) areas. Maximum attenuation of 47-49 dBA of noise level was found at worker’s colony and may be attributed mainly to the ground absorption. As the air quality standards of the area in respect of noise in the ambient is tending to increase, engineering control measures suggested to the noisiest equipments for better economically viable and higher payback period.

Comparison of a dipstick enzyme-linked immunosorbent assay with commercial assays for detection of Japanese encephalitis virus-specific IgM antibodies.

BACKGROUND: Japanese encephalitis (JE) is a major public health concern in Asia including India. Objectives: To evaluate an in-house developed dipstick enzyme-linked immunosorbent assay (ELISA) test vis-à-vis two commercial kits for detection of JE virus-specific IgM antibodies. SETTING AND DESIGN: Comparative study carried out in Research and Development centre. MATERIALS AND METHODS: A total of 136 specimens comprising 84 serum and 52 CSF samples were tested by in-house dipstick ELISA, Pan-Bio IgM capture ELISA (Pan-Bio, Australia) and JEV CheX IgM capture ELISA (XCyton, India). RESULTS: The overall agreement among all three tests was found to be 92% with both serum and cerebrospinal fluid (CSF) samples. The sensitivity of the dipstick ELISA was found to be 91% with serum and 89% with CSF samples respectively. The specificity of the dipstick ELISA with reference to both commercial assays was found to be 100% in serum and CSF samples in this study. CONCLUSIONS: The in-house dipstick ELISA with its comparable sensitivity and specificity can be used as a promising test in field conditions since it is simple, rapid and requires no specialized equipment.

Malarial hepatitis as a component of multiorgan failure--a bad prognostic sign.

A prospective study among the patients (n = 301) belonging to the coastal districts of Orissa having complicated falciparum malaria with multiorgan failure fulfilling modified APACHE II criteria, for a period of two years in this hospital setting was carried out with particular emphasis on hepatic involvement. There were 206 males and the rest females. Hepatic involvement in the form of raised serum bilirubin levels > or = 6 mg% and prothombin time > 4 compared to controls was found in 192 cases (63.8%). On analysis out of 192 cases predominantly conjugated hyperbilirubinaemia, mixed patterns and unconjugated hyperbilirubinaemia were seen in 115 (59.9%), 64 (33.3%) and 13 (6.8%) cases respectively. Serum bilirubin ranged from 6 to 38 mg%. Aminotransferase aspartate (AST, SGOT) and aminotransferase alkaline (ALT, SGPT) were raised almost two-fold in 98% cases of multiorgan failure with hepatic failure with mean values of 78 +/- 30.4 IU/l and 81 +/- 29.06 IU/l respectively. Nearly three-fold elevation of alkaline phosphatase was observed in 80% cases with mean (315 +/- 39.4 IU/l). Prothombin time was prolonged with mean 7 +/- 3 seconds. Serum proteins and albumin/globulin ratio were normal. There was no difference in glycaemic status over controls. In selected cases, liver histopathological study showed abnormalities in the form of Kupffer cell hyperplasia, mononuclear cell infiltration, hepatocyte necrosis, fatty changes and cholestasis. Majority of patients in multiorgan failure who died, had hepatic failure.

Fusogenic peptide as diagnostic marker for detection of flaviviruses.

BACKGROUND: Dengue, Japanese encephalitis, West Nile encephalitis, yellow fever are the common flaviviral diseases associated with high morbidity and mortality. The initial symptoms of most of the flaviviral infections are similar to each other as well as to some other viral diseases. Making clinical diagnosis, therefore, becomes a challenging task for the clinician. Several studies have been reported on using detection of serum antibodies against flavivirus for the diagnosis of specific flaviviral disease; no field-based pan-flavi virus detection system is available, which can be used in low-endemicity areas for differentiation of flaviviral disease from other viral diseases. AIM: To identify a conserved amino acid sequence among all flaviviruses and evaluate the antibody formed against the conserved peptide to develop pan-flavivirus detection system. MATERIALS AND METHODS: In the present study we have compared amino acid sequences of several flaviviruses and identified a conserved amino acid sequence lying in domain II of envelope protein. RESULTS: A peptide having the conserved amino acid sequence was used to generate polyclonal antibodies and these antibodies were used to detect several flaviviruses. Anti-peptide polyclonal antibodies selectively recognized flaviviruses and did not detect non-flaviviruses. Anti-peptide antibodies detected presence of virus in serum spiked with pure virus preparations. CONCLUSION: The study offers a rationale for development of pan-flavivirus capture assay suitable for low endemic areas.

Transcatheter occlusion of a large pulmonary arteriovenous malformation.

We report a patient with a large pulmonary arteriovenous malformation complicated by cerebral abscess. He was successfully treated by transcatheter embolization using bioptome-assisted delivery of multiple coils.

Serological & virological investigation of an outbreak of dengue fever in Gwalior, India.

BACKGROUND & OBJECTIVES: An outbreak of febrile illness occurred between September to November 2001 in Gwalior, Madhya Pradesh affecting individuals mostly in the age group < 30 yr. A total of 312 febrile indoor patients suspected to have dengue infection were investigated. METHODS: The investigation included examination of blood samples from patients for dengue specific IgM and IgG antibodies, isolation of virus in suckling mouse pups and in C(6/36) cell line followed by confirmation and typing through reverse transcriptase-PCR and nested PCR. RESULTS: The serological analysis of the 312 samples indicated 65 per cent positivity of which 21 per cent are of recent infection as indicated by the presence of IgM antibody and 78 per cent are found to be secondary in nature by showing the presence of IgG and/or IgM antibodies. The RT-PCR analysis of patients' sera employing dengue virus group specific conserved amplimer confirmed the etiological agent as dengue complex by showing the characteristic 511 bp amplicons. None of the antibody positive samples were found to be positive by RT-PCR. A total of 13 (6%) samples positive by RT-PCR, were processed for virus isolation in mouse pups and in C(6/36) cells. Of these 9 samples (80%) were confirmed positive for virus isolation as identified by RT-PCR. INTERPRETATION & CONCLUSION: The typing of isolates by nested PCR employing serotype specific amplimer revealed 119 bp amplicon characteristic of dengue virus type-2 and thus confirming the outbreak attributed to dengue virus type-2.

Use of radiofrequency ablation in the modified maze procedure.

Atrial fibrillation secondary to long-standing mitral valve disease is very common. The maze procedure carried out along with mitral valve surgery reverts many of these patients back to sinus rhythm. Using radiofrequency ablation to carry out the maze procedure during mitral valve surgery gives results comparable to those from the Cox surgical maze procedure. We present our experience with 3 patients of rheumatic mitral valvular disease in whom radiofrequency ablation was used for the maze procedure.

Teratoma masquerading as catamenial pleural effusion.

Pleural effusion is a common clinical entity in medical practice. We report a case wherein extensive investigations failed to yield a diagnosis and medical management including repeated thoracocentesis left the effusion refractory. The patient, a 26 years lady, gave a definite history of catamenial dry cough and wheeze. The mystery was unraveled following exploratory thoracotomy when a giant mediastinal teratomatous cyst with luteinized ovarian tissue was discovered and removed, leading to eventual cure for the patient.

Atrial fibrillation in patients with pure isolated severe rheumatic mitral regurgitation.

OBJECTIVE: This study examines the significance of the parameters that identify patients with mitral regurgitation (MR) and atrial fibrillation (AF) and discusses the indications for surgery in such patients. METHODS: Patients with MR and chronic AF (group I, n=64) and those without AF (group II, n=138) were studied by clinical and echocardiographic methods. Stepwise regression analysis identified factors associated with the presence of atrial fibrillation. RESULTS: Group I patients were older and more symptomatic. They had larger left ventricular (LV) end systolic dimension (4.6+/-1.1 cm vs 3.8+/-0.8 cm, p=0.03), left atrial (LA) dimension (5.4+/-2.0 cm vs 4.1+/-1.3 cm, p=0.02), LA area (55.9+/-27.1 cm2 vs 35.9+/-17.5 cm, p=0.003) and lower LV ejection fraction (58.8+/-8.0% vs 72.4+/-7.4%, p=0.0003). Right ventricular systolic pressure was higher (57.6+/-18.1 mm Hg vs 33.6+/-12.1 mm Hg, p=0.02). By stepwise regression analysis, factors that predicted the presence of AF were age (p < 0.03) and LA dimension (p < 0.01). A higher LV end systolic dimension and lower LV ejection fraction than the recommended value for good operative outcome were present in them. Emerging indications for surgery and predictors of poor outcome were seen. CONCLUSIONS: Atrial fibrillation in MR indicates a more chronic and severe disease process with worsening of left as well as right sided haemodynamics in spite of digoxin. Drifting towards decompensation, these patients are likely candidates for early surgery.