Occurrence of co-infection with dengue viruses during 2014 in New Delhi, India.

Dengue fever is an arthropod-borne viral infection that has become endemic in several parts of India including Delhi. We studied occurrence of co-infection with dengue viruses during an outbreak in New Delhi, India in 2014. For the present study, blood samples collected from symptomatic patients were analysed by RT-PCR. Eighty percent of the samples were positive for dengue virus. The result showed that DENV-1 (77%) was the predominant serotype followed by DENV-2 (60%). Concurrent infection with more than one serotype was identified in 43% of the positive samples. Phylogenetic analysis clustered DENV-1 strains with the American African and DENV-2 strains in Cosmopolitan genotypes. Four common amino-acid mutations were identified in the envelope gene of DENV-1 sequences (F337I, A369T, V380I and L402F) and one common mutation (N390S) in the DENV-2 sequences. Further analysis revealed purifying selection in both the serotypes. A significant number of patients were co-infected with DENV-1 and DENV-2 serotypes. Although we do not have direct evidence to demonstrate co-evolution of these two stereotypes, nonetheless their simultaneous occurrence does indicate that they are favoured by evolutionary forces. An ongoing surveillance and careful analysis of future outbreaks will strengthen the concept of co-evolution or otherwise. Whether the concurrent dengue viral infection is correlated with disease severity in a given population is another aspect to be pursued. This study is envisaged to be useful for future reference in the context of overall epidemiology.

Antiviral drug profile of human influenza A & B viruses circulating in India: 2004-2011.

BACKGROUND & OBJECTIVES: Recent influenza antiviral resistance studies in South East Asia, Europe and the United States reveal adamantane and neuraminidase inhibitor (NAIs) resistance. This study was undertaken to evaluate antiviral resistance in influenza viruses isolated from various parts of India, during 2004 to 2011. METHODS: Influenza viruses were analyzed genetically for known resistance markers by M2 and NA gene sequencing. Influenza A/H1N1 (n=206), A/H3N2 (n=371) viruses for amantadine resistance and A/H1N1 (n=206), A/H3N2 (n=272) and type B (n=326) for oseltamivir resistance were sequenced. Pandemic (H1N1) (n=493) isolates were tested for H274Y mutation by real time reverse transcription (rRT)-PCR. Randomly selected resistant and sensitive influenza A/H1N1 and A/H3N2 viruses were confirmed by phenotypic assay. RESULTS: Serine to asparagine (S3IN) mutation was detected in six isolates of 2007-2008. One dual-resistant A/H1N1 was detected for the first time in India with leucine to phenylalanine (L26F) mutation in M2 gene and H274Y mutation in NA gene. A/H3N2 viruses showed an increase in resistance to amantadine from 22.5 per cent in 2005 to 100 per cent in 2008 onwards with S3IN mutation. Fifty of the 61 (82%) A/H1N1 viruses tested in 2008-2009 were oseltamivir resistant with H274Y mutation, while all A/H3N2, pandemic A/H1N1 and type B isolates remained sensitive. Genetic results were also confirmed by phenotypic analysis of randomly selected 50 resistant A/H1N1 and 40 sensitive A/H3N2 isolates. INTERPRETATION & CONCLUSIONS: Emergence of influenza viruses resistant to amantadine and oseltamivir in spite of negligible usage of antivirals emphasizes the need for continuous monitoring of antiviral resistance.

Human metapneumovirus: a new respiratory pathogen.

Human metapneumovirus is a recently recognized pathogen of acute respiratory tract infection (ARI) in children as well as elderly and immunocompromised adults.The virus belongs to the family Paramyxoviridae, sub family Pneumovirinae and genus Metapneumovirus. Through genetic analysis it has been characterized into two groups A and B which are further divided into four sub-lineages. The virus is difficult to grow in tissue culture and hence reverse transcriptase-polymerase chain reaction (RT-PCR) for N and L gene is the method of choice for diagnosis. The virus has been seen in all countries with seasonal distribution in winter months for temperate and spring/summer for tropical countries. F gene is the most conserved among different lineages and efforts are underway to design recombination vaccine using F gene.

Cholesterol reduces the effects of dihydroxy bile acids and fatty acids on water and solute transport in the human jejunum.

Jejunal perfusion studies were performed in 16 healthy volunteers to test the hypothesis that intraluminal cholesterol can mitigate the fluid secretion induced by dihydroxy bile acids and fatty acids. Fluid secretion in the presence of 5 mM taurodeoxycholate was somewhat reduced by 4 mM mono-olein which was used for the solubilization of cholesterol. Addition of 0.8 mM cholesterol reduced fluid secretion further (P less than 0.05). Fluid secretion induced by 4 mM oleic acid was changed to net absorption in a linear fashion with increasing cholesterol concentration in the perfusion solutions. 1 mM cholesterol reduced fluid secretion induced by 6 mM oleic acid (P less than 0.005), but had no effect on fluid secretion induced by 6 mM linolenic acid. Glucose absorption was generally affected in a similar manner as water transport. In vitro, 1 mM cholesterol reduced monomer activity of 6 mM oleic acid to 72.3 +/- 0.9% of control and that of linolenic acid to 81.1 +/- 1.7% of control. Although statistically significant (P less than 0.001), the difference in the effects of cholesterol on monomer activities of the two fatty acids was rather small and it is unlikely that changes in monomer concentration of fatty acids and bile acids account for the protective effect of cholesterol. The in vivo observations point to a new physiological role for biliary cholesterol: the modification of the response of the small intestine to the effects of dihydroxy bile acids and fatty acids.

Duodenal angiomyolipoma: a case report.

The authors present a case of duodenal angiomyolipoma. Angiomyolipoma is a benign neoplasm, the most common site being the kidney. Extrarenal angiomyolipomas are rare. Only one case of duodenal angiomyolipoma has been reported. A 66 year old man presented with GI bleeding for two years. Endoscopy revealed a duodenal polyp which on histopathology revealed features of angiomyolipoma. On immunohistochemistry, smooth muscle component was positive for Smooth Muscle Actin. HMB-45 showed mild focal positivity. Patient had no history of tuberous sclerosis. Surgical excision of angiomyolipoma is usually curative with rare cases of local recurrence.

Dengue fever with papilledema: a case of dengue-3 virus infection in central nervous system.

BACKGROUND AND OBJECTIVES: Neurological manifestations of dengue fever are rarely reported during acute illness and clinical presentation commonly observed is of acute encephalitis or one of the post-infectious immune mediated manifestations. We describe a case of dengue fever having mild encephalopathy and papilledema at presentation. CASE REPORT: Twenty-year-old female presented with fever, headache and vomiting. On examination she did not have classical signs of dengue fever and was found to have bilateral papilledema on fundus examination. Detailed work-up did not reveal any other cause of papilledema. Diagnosis of dengue fever was established by blood IgM antibody test on day 7 of illness. Retrospective analysis of CSF (drawn on day 5 of illness) by RT-PCR assay showed a characteristic band of dengue-3 virus. Papilledema was transient and subsided following symptomatic treatment. The patient recovered from acute illness and follow-up was unremarkable. CONCLUSION: Especially in dengue endemic areas, in the patients having acute febrile illness with subtle signs and symptoms suggestive of CNS involvement, dengue virus infection should also be ruled out early in the clinical course.

Portal hypertensive gastropathy and gastric antral vascular ectasia.

Portal hypertensive gastropathy (PHG) and gastric antral vascular ectasia (GAVE) are gastric mucosal lesions that mostly present as chronic anemia and rarely cause the acute gastrointestinal hemorrhage. Despite similar clinical manifestations, their pathophysiology and management are entirely different. PHG is seen exclusively in patients with portal hypertension, but GAVE can also be observed in patients with other conditions. Their diagnosis is endoscopic, and although generally each of them has a characteristic endoscopic appearance and distribution, there are cases in which the differential is difficult and must rely on histology. This review focuses on the management of both entities. The mainstay of management of PHG is based on portal-hypotensive pharmacological treatment while GAVE benefits from hormonal therapy, endoscopic Nd:YAG laser, and argon plasma coagulation. More invasive options should be reserved for refractory cases.

Comparison of multiplex RT-PCR with virus isolation for detection, typing and sub-typing of influenza virus from influenza-like illness cases.

PURPOSE: Influenza epidemics and periodic pandemics occur worldwide resulting in significant mortality, morbidity and economic loss. There is need for a sensitive, rapid and cost-effective assay to detect, type and sub-type influenza viruses, as cell culture has a long turnaround time. MATERIALS AND METHODS: Nasopharyngeal swabs were collected from patients presenting with influenza-like illness (ILI) at AIIMS OPD and Primary Health Centre Ballabhgarh (Haryana). From June 2007 to January 2009 and then from September to November 2009, of 1567 specimens collected, 544 were randomly selected and were tested by virus culture using Madin-Darby Canine Kidney (MDCK) cells and by reverse transcription polymerase chain reaction (RT-PCR) for influenza A using primers for matrix gene and for influenza B using non-structural gene (NS) primers. All influenza A positives were sub-typed using primers for HA and NA genes of A/H1, A/H3. A separate multiplex RT-PCR having primers from matrix and HA genes of pandemic A (H1N1) pdm09 viruses was carried out on samples collected after September 2009. RESULTS: Of the 544 samples, 136 (25%) were positive for influenza by RT-PCR. Further typing analysis revealed 86 (63.2%) were typed as influenza A and 47 (34.5%) as influenza B viruses and 3 (2%) samples showed dual infection with influenza A and B. Of the 86 influenza A positive samples 48 (55.8%) were identified as seasonal influenza A/H1N1, 22 (25.6%) as A (H1N1) pdm09 and 16 (18.6%) as A/H3N2. Comparison of influenza positivity using virus culture revealed that only 97/136 (71.3%) were influenza positive. Sensitivity of viral detection was lowest for seasonal A/H1 (26/48; 54%), followed by H3N2 (11/16; 68.7%) and influenza B (38/47; 80.8%); all influenza A/H1N1pdm09 viruses were detected by both methods. CONCLUSION: RT-PCR is a sensitive, low cost and rapid screening test for diagnosing influenza infection during epidemics and pandemics. mRT-PCR increased the detection rates for influenza by 28.6% as compared with virus isolation and thus is a useful assay in both diagnostic and epidemiological settings in resource poor countries.

Stimulation of HIV replication in mononuclear phagocytes by leukemia inhibitory factor.

This study examined the effects of leukemia inhibitory factor (LIF) on human immunodeficiency virus (HIV) replication in mononuclear phagocytes (MNP). LIF induced a dose-dependent increase in p24 antigen production in the chronically infected promonocytic cell line U1. The magnitude and time kinetics of the LIF effects were similar to interleukin 1 (IL-1), IL-6, and tumor necrosis factor (TNF), other cytokines known to induce HIV replication in this cell line. To characterize mechanisms responsible for these LIF effects, levels of HIV mRNA, activation of the DNA binding protein nuclear factor (NF)-kB, signal transduction pathways, and potential interactions with other cytokines were analyzed. LIF increased steady-state levels of HIV mRNA at 2.0, 4.3, and 9.2 kB. This was detectable by 24 h and persisted until 72 h. The DNA binding protein NF-kB is a central mediator in cytokine activation of HIV transcription. NF-kB levels were higher in unstimulated U1 cells as compared to the parent cell line U937. In both cell lines LIF increased NF-kB activity. Induction of NF-kB and HIV replication by cytokines are at least in part dependent on reactive oxygen intermediates. The oxygen radical scavenger N-acetyl-L-cysteine, but not an inhibitor of nitric oxide synthase, inhibited LIF-induced HIV replication. LIF induces the production of other cytokines in monocytes but its effects on HIV replication were not inhibited by antibodies to IL-1, TNF, or IL-6. These results identify LIF as a stimulus of HIV replication.(ABSTRACT TRUNCATED AT 250 WORDS)

Rapid detection of respiratory viruses by centrifugation enhanced cultures from children with acute lower respiratory tract infections.

BACKGROUND: Acute respiratory tract infection (ARI) is the major cause of morbidity and mortality in young children in developing countries. Information on viral aetiology in ARI in India is very limited. OBJECTIVE: The aim of the study was to define the role of viruses in acute lower respiratory tract infections (ALRTI) in children in India using centrifugation enhanced cultures followed by indirect immunofluorescence (IIF). STUDY DESIGN: Nasopharyngeal aspirates (NPAs) were collected from children from September 1995 to April 1997, attending paediatric clinic of All India Institute of Medical Sciences (AIIMS) with symptoms of ALRTI. Virus isolation was done by centrifugation enhanced cultures using HEp-2, LLC-MK2 and MDCK cells. The viruses were identified at 24-48 h post inoculation by IIF staining using monoclonal antibodies to respiratory syncytial virus (RSV), parainfluenza virus (PIV), influenza virus and adenovirus. RESULTS: Of 200 NPA samples, 89 (44.5%) were positive for one or more viral pathogens. RSV was detected in 34 (17%) of all ALRTI cases followed by influenza viruses in 29 (14.5%), PIVs in 23 (11.5%) and adenoviruses in three (1.5%). In 79 children with bronchiolitis, RSV was most frequently isolated (25%) pathogen, while in bronchopneumonia cases (101) the most common viral pathogen was influenza virus (17%). In eight cases (4%) of ALRTI dual infections were detected. In 100 NPA specimens IIF staining on direct cell smears was carried out and viruses were detected in only 17%. RSV and influenza virus infection peaked from September to December, where as PIV infections were more frequent from January to April. CONCLUSION: Respiratory viruses accounted for 44.5% of cases of ALRTI in India and the results of viral aetiology could be given in 24-48 h using centrifugation enhanced cultures. RSV was the most common viral agent associated with ALRTI in children under 5 years of age with greater association with bronchiolitis.

Rapid detection of rotavirus by using colloidal gold particles labeled with monoclonal antibody.

A rapid single-step, sensitive and specific immunogold assay is described for detection of rotavirus. Murine monoclonal antibody (MCA) to the group antigen of rotavirus was dotted on a nitrocellulose paper strip. This was used to capture the rotavirus antigen which was revealed using a conjugate consisting of the MCA conjugated to gold particles. This assay detects 5 x 10(7) particles of rotavirus. It also acutely detected rotavirus from fecal samples, but failed to show any reaction with microscopically confirmed fecal samples containing G. lamblia and E. histolytica. The time taken for the test was approximately 10 min. Its versatility, simplicity, sensitivity and specificity makes it useful for third world countries.

Cimetidine in the treatment of non-ulcer dyspepsia: results of a randomized double-blind, placebo-controlled study.

A randomized double-blind, placebo-controlled study was carried out in 56 patients with essential dyspepsia to investigate the therapeutic efficacy of cimetidine in providing symptomatic relief. Patients received either 1 tablet of cimetidine (400 mg) or identical looking placebo twice daily for a period of 4 weeks. A detailed symptomatic assessment was made at weekly intervals. Abdominal pain, the primary symptom, was relieved in a higher proportion of cimetidine-treated patients compared to placebo group (67% versus 40%, p less than 0.05). Most of the secondary gastro-intestinal symptoms also improved in a higher proportion of patients in the cimetidine group although the difference was statistically not significant. The outcome of treatment was not influenced by factors such as duration of disease, initial severity of pain and smoking habits of the patient.

Dengue haemorrhagic fever in children in the 1996 Delhi epidemic.

An epidemic of dengue haemorrhagic fever (DHF) occurred in Delhi in 1996. A total of 240 children between the age of 4 months to 13 years of either sex, admitted in one hospital, were evaluated. Two hundred and sixteen (90%) children were from Delhi. A clinical diagnosis of dengue fever (DF) was made in 25 (10%), dengue fever with unusual bleeding (DFB) in 22 (9%), DHF in 80 (33%) and dengue shock syndrome (DSS) in 113 (47%) of the children strictly according to the WHO classification. The age peaked at 8 years. There was no association between various grades of severity of illness and age-groups though girls suffered from more severe illness. No association between severity of malnutrition and severity of illness was observed. Tourniquet test was positive in 40% with DF, 18% with DFB, 62% with DHF and 64% with DSS. In DSS haematemesis was present in 55 (49%), epistaxis in 39 (35%), melaena in 27 (24%) and ecchymosis in 34 (30%) patients. Children diagnosed as DFB had haematemesis and epistaxis in 12 (55%) and 10 (45%) respectively. Intravenous fluid requirement was clearly less in DFB patients than in DHF/DSS patients. Unusual clinical features in the form of jaundice were present in 7 (6%), hepatic encephalopathy in 6 (5%) and dengue encephalopathy in 6 (5%) patients. Dengue 2 virus was isolated from 10 of the 50 patients for whom viral culture was done on C6/36 clone of Aedes albopictus cell line. Eighteen patients suffering from DSS died giving an overall case fatality of 7.5%. The mortality rate in DHF/DSS was 9.3%. It is further suggested that DFB is a distinct entity. Most patients could be classified by the WHO classification if a retrospective packed cell volume was used to assess haemoconcentration. We suggest that development of area-specific criteria for diagnosis and management is desirable.

Clinical profile of biopsy proven idiopathic myocarditis.

We studied 20 patients in detail (age: 27 months to 45 years, mean 22 years; 15 males, 5 females) of idiopathic myocarditis histologically confirmed by endomyocardial biopsy. None of these patients had evidence of active or previous rheumatic fever. The commonest mode of presentation was congestive heart failure (16 patients) followed by arrhythmias (seven patients--five of whom had associated congestive heart failure) and chest pain resembling myocardial infarction (two patients). Ten patients had a history of preceding upper respiratory infection. Only one of these patients had a significant rising serum titre for Coxsackie B3 virus. Throat and rectal swabs for virus culture were negative in all patients. The electrocardiogram was abnormal in all patients, with a prolonged corrected QT-interval being the commonest abnormality (14 patients). Serial electrocardiographic patterns of evolving myocardial infarction occurred in three patients. Echocardiographic left ventricular end diastolic dimension (4.15 +/- 1.01 cm/m2) and end systolic dimension (3.37 +/- 1.03 cm/m2) were increased in 15 of the 18 patients studied. Pericardial involvement occurred in only one patient. Radionuclide ventriculography showed a reduced left ventricular ejection fraction (< 50%) in 17 patients, global hypokinesia in 12 patients and regional wall motion abnormalities in five patients. Left ventricular and right ventricular end diastolic pressures were elevated in 15 and 11 patients, respectively.

Nocturnal gastric acid secretion in duodenal ulcer: inhibition by cimetidine.

The inhibitory effect of cimetidine 200 mg, cimetidine 400 mg, cimetidine 200 mg + oxyphenonium bromide 10 mg and placebo was studied on nocturnal gastric acid secretion in 10 patients with duodenal ulcer. Each patient was studied over a period of four nights and trial medication was given in a randomized sequence. Cimetidine in both doses significantly inhibited the nocturnal gastric acid secretion. The drug reduced both the H+ concentration and gastric juice volume but the reduction of H+ concentration was more impressive. Mean percentage inhibition of nocturnal acid output with cimetidine 400 mg (89.6 +/- 2.868) was significantly higher than cimetidine 200 mg (80.3 +/- 4.085; p less than 0.01). Combination of cimetidine 200 mg and oxyphenonium bromide 10 mg was significantly better than cimetidine 200 mg alone (p less than 0.05) and this combination produced inhibition of gastric juice volume, H+ concentration and acid output comparable to cimetidine 400 mg.

Hormone producing pancreatic islet cell carcinoma: changing clinical presentation.

A patient with pancreatic islet cell carcinoma demonstrated spontaneous remission and recurrence of hyperinsulinism and disappearance of elevated plasma motilin levels. Despite evidence for gastrin production by the tumor initially, the Zollinger-Ellison syndrome was not diagnosed until three years after initial presentation. Diarrhea and steatorrhea could be attributed to hyperchlorhydria rather than to direct intestinal effects of elevated cirulating gastrin, gastric inhibitory peptide or motilin. Pancreatic islet cell carcinomas, considered as a type a APUD cell proliferation, frequently produce more than one hormone; the pattern of hormone secretion may differ with time and clinical manifestations may change accordingly.

A nonradioisotopic reverse phase dipstick hybridization method for detection of polymerase chain reaction amplified product.

A rapid and simple nonradioisotopic method has been developed for detection of polymerase chain reaction (PCR) amplified product. Digoxigenin-11-dUTP (DIG-11-dUTP) was incorporated in the amplified product by including it in the PCR reaction mixture. The PCR product was detected colorimetrically either directly or by reverse phase hybridization method where an unlabelled oligo-nucleotide probe was immobilized on a nitrocellulose dipstick and the digoxigenin labelled PCR product was in the liquid phase. With this system the PCR product could be detected even after 10 cycles of amplification by both direct and hybridization methods. The method was applied on the amplified product of DNA from peripheral blood mononuclear cells from 10 HIV-1 ELISA positive and 8 ELISA negative individuals. PCR was positive in all ELISA positive, Western blot positive individuals from whom HIV-1 was also isolated. PCR was negative in all ELISA negative individuals.

Acute rubella infection in pregnant women in Delhi.

Serum samples of 17 pregnant women with suspected rubella who presented at the Department of Microbiology, AIIMS, New Delhi, from March to May 1988 for confirmation of diagnosis were tested for rubella haemagglutination inhibiting (HAI) antibodies and rubella specific IgM antibodies by mu-capture ELISA. Ten of the 17 women were diagnosed to have acute rubella infection as they showed the presence of rubella specific IgM antibodies. Nine of these gave history of fever and rash whereas one woman remained asymptomatic. These observations suggest an increase in the incidence of rubella infection in pregnant women from March to May 1988 in Delhi.

An epidemic of acute haemorrhagic conjunctivitis caused by coxsackie A24 variant.

An epidemic of acute haemorrhagic conjunctivitis (AHC) caused by a variant of coxsackie A24 (cox A24) occurred in Delhi during August to September 1988. Cox A24 antigen was detected by indirect immunofluorescence (IFA) in conjunctival cell smears of 13 of the 38 (34.2%) patients studied. Virus was isolated from conjunctival swabs in 11 (28.9%) patients and all isolates were neutralized by cox A24 antiserum. Five virus strains sent to Virology Division of Centres for Disease Control, Atlanta, USA, were confirmed as cox A24 variant. Enterovirus type 70 (EV70) was not demonstrable either by IFA or neutralization tests. Conjunctival swabs from 10 healthy laboratory controls did not show any evidence of EV70 or cox A24 virus or their antigens.

Molecular epidemiology of human rotavirus infections in Chandigarh (India).

Molecular epidemiology of rotavirus infections was studied in children with acute gastroenteritis attending the Nehru Hospital, Chandigarh. A total of 87 stool samples were studied for RNA migration pattern by polyacrylamide gel electropherosis. Only 33 strains could be electropherotyped and two different RNA types 'Short' and 'Long' were observed. Fifteen had a Short RNA pattern and 18 had a Long RNA pattern. There were no intergenomic variations between the Short or Long RNA types. On analysis of subgroup specificity by ELISA using monoclonal antibodies, all Long strains belonged to subgroup 2 and all Short strains to subgroup 1. Our results show that only two electropherotypes were prevalent in the area studied and during a particular peak of infection, only one electropherotype was predominant.