Association Between Leucopenia, Transaminitis, Nonstructural Protein One Antigen (Ns1Ag) Level, and Thrombocytopenia in Adult Dengue Patients in a Tertiary Care Hospital: A Cross-Sectional Study.

BACKGROUND: The dengue virus is present throughout the tropics. Thrombocytopenia is one of the severe manifestations of the dengue virus. We studied the association of thrombocytopenia with serum transaminase level, leucopenia, and nonstructural protein one antigen (Ns1Ag) level. METHODS: Data were taken retrospectively from hospital records after obtaining ethical committee approval. In the study, we included 102 patients with acute febrile illness with clinical features suggestive of dengue fever (dengue Ns1Ag positive, dengue IgM positive, or both). We excluded patients with thrombocytopenia due to other causes. Patients' demographic, clinical, and laboratory parameters were collected. We also noted episodes of bleeding or the need for a platelet transfusion. We did a statistical analysis to find out the correlation between age, sex, leucopenia, transaminitis, Ns1Ag level, and thrombocytopenia and its severity. RESULTS: Multiple regression analysis was used to find thrombocytopenia predictors among aspartate transaminase (AST), alanine transaminase (ALT), Ns1Ag level, and leucopenia. AST and ALT correlated inversely with thrombocytopenia, with p-values of 0.012 and 0.027, respectively. Ns1Ag and leucopenia were not associated with thrombocytopenia, with p-values of 0.802 and 0.532, respectively (p-values significant at 0.01<= p<=0.05). CONCLUSION: Serum AST and ALT levels correlate with thrombocytopenia in dengue fever.

Neurological Manifestations of Perinatal Dengue.

Dengue viruses (DENVs) are single-stranded RNA viruses belonging to the family Flaviviridae. There are four distinct antigenically related serotypes, DENVs types 1, 2, 3, and 4. These are all mosquito-borne human pathogens. Congenital dengue disease occurs when there is mother-to-fetus transmission of the virus and should be suspected in endemic regions in neonates presenting with fever, maculopapular rash, and thrombocytopenia. Although most of the infected infants remain asymptomatic, some can develop clinical manifestations such as sepsis-like illness, gastric bleeding, circulatory failure, and death. Neurological manifestations include intracerebral hemorrhages, neurological malformations, and acute focal/disseminated encephalitis/encephalomyelitis. Dengue NS1Ag, a highly conserved glycoprotein, can help the detection of cases in the viremic stage. We do not have proven specific therapies yet; management is largely supportive and is focused on close monitoring and maintaining adequate intravascular volume.

Dengue Immunological Markers Evolution at Saint Camille Hospital in Ouagadougou (HOSCO) Burkina Faso.

<b>Background and Objective:</b> Dengue is a remerging vector-borne viral disease in Burkina Faso since the outbreak of 2013 and requires special attention from health authorities. This study reports the prevalence of dengue fever serological markers (NS1Ag, IgM and IgG) and infection dynamic from January, 2018 to December, 2020 among patients tested for dengue infection at Saint Camille Hospital of Ouagadougou (HOSCO). <b>Materials and Methods:</b> The study population consisted of 6414 patients aged 0-97 years. Dengue virus infection was detected in serum or plasma using the SD bioline dengue duo rapid detection kit. <b>Results:</b> The prevalence of dengue NS1Ag was 2.25% (45/2003), 18.43% (501/2719) and 2.42% (38/1569) in the study population in 2018, 2019 and 2020, respectively. The age groups over 50 years and 15-20 years were significantly more infected compared to the group 21-30 years respectively in 2019 (p = 0.030) and 2020 (p = 0.035). Patients tested positive for at least one of these markers (NSlAg, IgG and IgM) represented 26.01% (521/2003) and 38.98% (1060/2719). The peak of infection during 2018 and 2019 was observed between October and November. The present study reports a high seroprevalence of acute dengue virus infection. The presence of NS1Ag, IgM and IgG in patients suggests an active circulation of the dengue virus in Ouagadougou. <b>Conclusion:</b> Data shows recurrent outbreaks of dengue infection in our country need strong surveillance and a suitable and affordable diagnostic system to clarify the burden, pinpoint the risk factors and for better case management.

Dengue in children and young adults, a cross-sectional study from the western part of Uttar Pradesh.

BACKGROUND: Dengue has emerged as a major public health problem in India. It presents more aggressively among younger age groups as compared to adults. Therefore, it necessitates the accurate estimation of prevalence in younger age groups. MATERIALS AND METHOD: Of all the 1026 clinically suspected cases of dengue up to the age of 18 years were enrolled in this study and grouped into four age groups (Group I - <0 to 1 year, Group II- 1 to 6 years, Group III- 7 to 12 years, and Group IV- 13 to 18 years). Their blood samples were aseptically collected from different clinical departments and were submitted to the Viral Research and Diagnostic Laboratory (VRDL), Department of Microbiology during the outbreak of 2016-17. Serum was separated and processed for dengue Non Structural Protein 1 antigen (NS1 Ag)and Immunoglobuline M antibody (IgM Ab) enzyme-linked immunosorbent assay (ELISA). All the relevant variables like age, sex, and demographic profile were recorded and statistically analyzed. RESULTS: A total 295 of the 1026 cases were detected positive for dengue either by NS1 Ag or IgM Ab ELISA. The results show the susceptibility to dengue being increased in the order of age Group I to IV. We analyzed the outbreak of year 2016 and 2017, of these 159/483 (33%) cases and 136/543 (25%) cases, respectively, were found seropositive during these years. The months of September, October, and November are more prone to dengue infection. CONCLUSION: Group III and IV were more susceptible to dengue fever (DF). The months of postmonsoon season are more favorable for spread of dengue among different age groups of the population.

The Clinical and Serological Profile of Pediatric Dengue.

OBJECTIVE: To classify suspected dengue into dengue, dengue with warning signs and severe dengue, based on clinical features as per the revised WHO guidelines with special emphasis on serology. METHODS: It was a prospective cross-sectional study for five years from 2011-2016 in a tertiary care medical college hospital in Bangalore. All cases of fever of three to five days duration with symptoms like dengue were enrolled for the study. They were categorized into three groups as per the Revised WHO 2012 criteria. Laboratory parameters, serology, ultrasound abdomen and X-ray were done in almost all patients. Data was analysed by SPSS software, version 16, and different groups were compared with Chi square test. RESULTS: Five hundred sixty eight children were diagnosed to have dengue fever; 4.2% of the sample belonged to infancy. Majority were in the age group of 5-10 y (42.6%). Fever and flushing were present in majority of the children. Gastrointestinal bleed was more commonly seen in the severe dengue group. Dengue nonstructural protein antigen (NS1Ag) was positive in 78%, immunoglobulin M (IgM) in 15.8% and immunoglobulin G (IgG) in 14.6%. Children with IgG had more complications, though not statistically significant. Mortality was reported in 1.2%. Dengue serology helped to confirm the diagnosis, however did not help in patient management. CONCLUSIONS: There is a considerable overlap in the symptomatology of dengue with warning signs and severe dengue. More studies are required on the severity and type of response to treatment in infants and obese adoloscents with severe dengue.

Clinical applicability of various dengue diagnostic tests in resource-limited endemic settings.

INTRODUCTION: Dengue is one of the most important arboviral infections caused by one of the four dengue serotypes, 1-4. OBJECTIVE: To study the applicability of different diagnostic methods in diagnosis of dengue viral infection. MATERIALS AND METHODS: A total of 2101 blood samples were collected for confirmation of dengue viral infection. All the samples were tested by dengue-specific IgM ELISA, of which 111 were also tested for NS1 antigen detection and 27 acute samples (≤5 days) were further subjected for viral RNA detection by RT-PCR and isolation in C6/36 cell line. To detect the sensitivity of NS1 antigen for different dengue virus serotypes, four dengue serotype 1 and 12 dengue 3 were subjected for the NS1 antigen assay. RESULTS: Most common age group affected was 16-45 years, with male to female ratio of 2.8:1. During first 3 days of illness virus isolation and RT-PCR were the most sensitive (83%) followed by NS1 antigen detection (75%) and IgM detection (37.5%). The positivity of IgM detection was found to be significantly higher as compared to NS1 detection during 4 to 5 days and also after 5 days of illness (P < 0.05). Dengue serotypes 1 and 3 were found to be co-circulated, dengue 1 being the predominant serotype. CONCLUSION: Virus isolation and RT-PCR were the most sensitive tests during the early period of illness whereas beyond third day, IgM antibody detection was found to be the most sensitive method of dengue diagnosis.

Dengue-4 false negative results by Panbio® Dengue Early ELISA assay in Brazil.

BACKGROUND: Dengue is a serious public health problem in numerous countries. The ability to rapidly diagnosis dengue is important for patient triage and management. Detection of dengue viral protein, NS1, represents a new approach to dengue diagnosis. OBJECTIVE: The present study aims to evaluate if there are false negative results using the NS1 Ag rapid assay (Panbio(®) Dengue Early ELISA) in two different epidemiological situations (epidemic and non-epidemic). STUDY DESIGN: 220 serum samples from patients with clinical symptoms of classical dengue fever were tested by NS1 antigen capture ELISA and Multiplex-Nested-PCR. RESULTS: In samples collected in a non-epidemic period we found a 100% agreement of ELISA and RT-PCR in dengue negative samples and 85% agreement of ELISA and RT-PCR in dengue positive samples. But when we tested samples during an epidemic period (large DENV-4 outbreak) we found 15% false negative results (p<0.05) in dengue negative samples. CONCLUSIONS: Due to false negative results for DENV-4, the sole use of the Panbio(®) Dengue Early ELISA assay as a screening method for monitoring circulating dengue serotypes must be reevaluated.