Presence of diarrhea associated with better outcomes in patients with COVID-19 – A prospective evaluation

Purpose: Gastrointestinal (GI) manifestations have been well documented in patients with coronavirus disease 2019 (COVID-19), but its clinical impact on the course of the disease is debatable. Majority of the available data is retrospective, and hence this prospective study was planned to study the impact of GI symptoms on COVID-19 outcome. Methods: All COVID-19 patients admitted in a tertiary care centre from August–October 2020 were screened and patients without pre-existing GI diseases were included. A detailed history of the various symptoms including duration was documented. Various baseline laboratory investigations and inflammatory markers were conducted as per the protocol. Patients with and without diarrhea were compared for the various disease outcome parameters. Results: Of the 244 patients screened, 203 patients (128 males; 63.1%) were included. Respiratory symptoms alone were present in 49 (24.1%), GI symptoms alone in 20 (9.9%) and 117 (57.6%) had both. Overall GI symptoms was noted in 137 (67.5%) cases with the commonest being diarrhea (61; 30.0%). Patients with both respiratory and any GI symptoms showed a lower trend towards need for mechanical ventilation (12.2% vs 7.7%; p ¼ 0.35) and mortality (10.2% vs 4.3%; p ¼ 0.14) compared to respiratory symptoms alone, although not statistically significant. Patients with diarrhea (n ¼ 61) had no mortality (0% vs 7.7%; p ¼ 0.036) or need for mechanical ventilation and shorter hospital stay compared to those who did not have diarrhea. Conclusion: GI symptoms are frequent in patients with SARS-CoV-2 infection and the commonest is diarrhea. Diarrhea is a harbinger of better outcome with lower mortality among COVID-19 positive patients.

In silico study to predict promiscuous T cell and B cell-epitopes derived from the vaccine candidate antigens of Plasmodium vivax binding to MHC class-II alleles

Malaria is one of the major causes of health and disability globally, even after tremendous efforts to eradicate it. Till date no highly effective vaccine is available for its control. The primary reason for the low efficacy of vaccines is extensive polymorphism in potential vaccine candidate antigen genes and HLA polymorphisms in the human population. This problem can be resolved by developing a vaccine using promiscuous peptides to combine the number of HLA alleles. This study predicted T and B cell epitopes (promiscuous peptides) by targeting PPPK-DHPS and DHFR-TS proteins of Plasmodium vivax, using different in silico tools. Selected peptides were characterized as promiscuous peptides on the basis of their immunogenicity, antigenicity and hydrophobicity. Furthermore, to confirm their immunogenicity, these peptides were utilized for molecular modelling and docking analysis. For determining the requisite affinity with distinct HLA Class-I, and HLA Class-II alleles, only five peptides for DHFR-TS and 3 peptides for PPPK-DHPS were chosen as promiscuous peptides. The D1 peptide has the maximum binding energy with HLA alleles, according to HLA-peptide complex modelling and binding interaction analyses. These findings could lead to the development of epitope-based vaccinations with improved safety and efficacy. These epitopes could be major vaccine targets in P. vivax as they possess a higher number of promiscuous peptides. Also, the B cell epitopes possess maximum affinity towards different alleles as analyzed by docking scores. However, further investigation is warranted in vitro and in vivo.

Differential Effect of Paromomycin and Nitazoxanide on Clinical Isolates of Cryptosporidia In Vitro.

Background: Cryptosporidiosis is one of the most difficult protozoan infections to treat, with only two drugs i.e. nitazoxanide and paromomycin known for treatment with variable response in different patients. Human cryptosporidiosis is accounted mainly by C. hominis and C. parvum. These two species or their subtypes are known to differ in clinical manifestations, and may differ in their response to drugs. So, we planned the study to see the effect of nitazoxanide and paromomycin on different isolates of Cryptosporidium in vitro. Methods: MDCK cell lines were used for in vitro growth of parasite and cytotoxicity of drugs to MDCK cells was determined by MTT assay after 3, 12 and 24 hours of drug exposure. Efficacy of non-toxic drug concentrations (<25% cytotoxic) on 12 Cryptosporidium isolates (7 C. hominis and 5 C. parvum) was determined at three different life cycle stages (in vitro growth, invasion and oocyst) by quantitative RT-PCR. Unpaired t-test was used to calculate the difference response of Cryptosporidium isolates to nitazoxanide and paromomycin. Results and conclusions: Cytotoxicity of nitazoxanide and paromomycin increased in dose and time dependent manner. After 24 hours of drug exposure, >25% cytotoxic effect was seen with nitazoxanide and paromomycin at concentrations of more than, 25μg/ml and 6mg/ml, respectively. Nitazoxanide was more effective than paromomycin in decreasing in vitro growth, invasion inhibition and reducing oocyst viability of Cryptosporidium isolates. Drugs effect was higher on growth inhibition followed by invasion inhibition and least in decreasing oocyst viability. Different isolates had variable response to drugs; cumulatively C. parvum isolates were more susceptible at particular drug concentrations than C. hominis isolates.

Isosporiasis in a tertiary care center of North India.

Background: Cystoisospora (Isospora) belli is a coccidian, protozoan parasite that resides in the gastrointestinal tract of humans. It is mainly reported from HIV-positive individuals. However, a few cases have been reported in other immunosuppressed individuals including renal transplant patients, and those with lymphoma and leukemia. Materials and Methods: During a period of 5 years (2008-2012), approximately 1700 stool samples of immunosuppressed patients were screened for the presence of opportunistic parasitic infections by a modifi ed acid fast staining technique. Results: A total of 41 C. belli were reported, out of which 30 were HIV-positive individuals while 11 were HIV negative. The latter individuals were also immunosuppressed due to prolonged use of steroids or other immunosuppressive drugs. Twenty-six out of 30 HIVpositive patients and all the HIV-negative individuals with C. belli infection had diarrhea. Conclusion: All immunosuppressed individuals should be examined for the presence of opportunistic coccidian parasitic infections and treated accordingly and alternatively, isolation of opportunistic parasites should trigger a hunt for immunocompromised state to reduce the morbidity and mortality in such patients.

Multidrug resistance in amoebiasis patients.

BACKGROUND & OBJECTIVES: Amoebiasis, caused by Entamoeba sp. a protozoan parasite, is a major public health problem in tropical and subtropical countries. The symptomatic patients are treated by specific chemotherapy. However, there are reports of treatment failure in some cases suggesting the possibility of drug resistance. The present study was therefore planned to assess the presence and expression of mRNA of multidrug resistance (MDR) gene in clinical isolates of Entamoeba histolytica and E. dispar. METHODS: Forty five clinical isolates of Entamoeba sp. [E. histolytica (15) and E. dispar (30)] were maintained in polyxenic followed by monoxenic medium. DNA and total RNA were extracted from clinical isolates of Entamoeba sp. and from sensitive strain of E. histolytica (HM1: IMSS) and subjected to polymerase chain reaction (PCR) and multiplex reverse transcription (RT)-PCR techniques. RESULTS: The 344 bp segment of E. histolytica DNA was seen by PCR using primers specific to EhPgp1 in all clinical isolates and sensitive strain of E. histolytica. Over expression of EhPgp1 was observed only in resistant mutant of E. histolytica; however, transcription of EhPgp1 was not seen in any clinical isolates and sensitive strain of E. histolytica. INTERPRETATION & CONCLUSION: The findings of the present study indicate that, so far, drug resistance in clinical isolates of E. histolytica does not seem to be a major problem in this country. However, susceptibility of clinical isolates of E. histolytica against various antiamoebic drugs needs to be investigated for better management.

Comparative evaluation of hexokinase isoenzyme typing and antigen detection for differentiation of Entamoeba histolytica and Entamoeba dispar.

Entamoeba histolytica, the causative organism of invasive amebiasis is a potential pathogen, while asymptomatic infection is caused by E. dispar. Differentiation of the species is not possible on the basis of morphological characters by microscopic examination. In the present study an attempt has been made to differentiate E. histolytica from E. dispar in 45 isolates obtained from culture and direct stool samples respectively on the basis of hexokinase isoenzyme analysis and Tech Lab ELISA. A 100% correlation was found between these two techniques. However, Tech Lab E. histolytica antigen detection test was found to be both rapid and technically simple. Its use in diagnosis and epidemiological studies is recommended.

Intestinal parasites and intra familial incidence in a low socio-economic area of Chandigarh (North India).

A total of 550 stool samples were collected from a low socio economic population of Chandigarh (North India) and examined macroscopically and microscopically, to determine the prevalence of intestinal parasitic infections and their familial incidence. The overall prevalence rate was 19.3%. Ascaris lumbricoides and Giardia lamblia were the commonest, affecting 51 (9.3%) and 33 (6.0%), respectively. In 17 (22.7%) families the same parasite was observed to infect multiple family members, which included A.lumbricoides (in 9 families), G. lamblia (in 7 families) and H. nana (in 1 family). The results of present study indicate that there is a high prevalence of parasitic infection in the community where personal hygiene and sanitary conditions are poor and may be one of the contributing factors for transmission within the families. Intervention strategies including health education program should be designed and implemented to control parasitic infections.