RESUMO
Many countries in the world are experiencing a recent surge in COVID-19 cases. This is mainly attributed to the emergence of new SARS-CoV-2 variants. Genome sequencing is the only means to detect the evolving virus mutants and emerging variants. Cycle threshold values have an inverse relationship with viral load and lower Ct values are also found to be associated with increased infectivity. In this study, we propose to use Ct values as an early indicator for upcoming COVID-19 waves. A retrospective cross-sectional study was carried out to analyze the Ct values of positive samples reported during the first wave and second wave (April 2020-May 2021). Median Ct values of confirmatory genes were taken into consideration for comparison. Ct values below 25, >25-30, and >30 were categorized as high, moderate, and low viral load respectively. Our study found a significantly higher proportion of positive samples with a low Ct value (<25) across age groups and gender during the second wave of the COVID-19 pandemic. A higher proportion of positive samples with a low Ct value (high viral load) may act as an early indicator of an upcoming surge.
Assuntos
Teste de Ácido Nucleico para COVID-19 , COVID-19/diagnóstico , COVID-19/epidemiologia , Adolescente , Adulto , Infecções Assintomáticas/epidemiologia , COVID-19/virologia , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , SARS-CoV-2/fisiologia , Carga Viral , Adulto JovemRESUMO
The unprecedented demand for testing for the ongoing coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 has led to an acute shortage and limited availability of test reagents for which pooling of samples has been recommended in areas with low prevalence. Considering the possibility of dilution factor in pool testing, an attempt was made to find out possibility of any true positive samples in pools with late amplification. The study was conducted on samples received from various collection centers in different districts of Odisha as well as from patients attending the screening clinic or admitted in COVID ward of the hospital. Nasal/nasopharyngeal/throat swabs received in viral transport media in cold chain were subjected to Real-time polymerase chain reaction (RT-PCR) testing in a Biosafety Laboratory level-2 by including uniform volume of four units (samples) per pool. All confirmed and probable positive pools in screening assay were de-convoluted and individual samples tested for confirmatory assay. Inclusion of an additional criteria of probable positive pool (Ct value >35 with non-sigmoid amplification curve or showing a line of amplification towards the end of the cycle) yielded 39 (15.5%) more true positive samples out of a total of 251 positive samples that would otherwise have been missed if only the classical criteria of positive (Ct within 35 with proper sigmoid curve) had been considered. The study highlights the importance of considering any indication of late amplification in the RT-PCR test to label a pool as positive to avoid missing any true positive sample in the pool.
Assuntos
Teste para COVID-19/métodos , COVID-19/diagnóstico , SARS-CoV-2/isolamento & purificação , Teste de Ácido Nucleico para COVID-19/métodos , Técnicas de Laboratório Clínico , Contenção de Riscos Biológicos , Testes Diagnósticos de Rotina , Humanos , Índia , Programas de Rastreamento , Reação em Cadeia da Polimerase em Tempo Real , SARS-CoV-2/genética , Sensibilidade e Especificidade , Manejo de Espécimes/métodosRESUMO
The performance of two artificial intelligence (AI) platforms, ChatGPT 3.5 (OpenAI, California, United States) and Gemini (Google AI, California, United States) was assessed by answering 200 questions of microbiology drawn from validated sources. The questions were selected from topics such as General Microbiology, Immunology, and Microbiology Applied to Infectious Diseases. The study was conducted from December 2023 to March 2024, and the responses of the different AI platforms were compared with an answer key. Statistical analysis was performed to assess accuracy. ChatGPT 3.5 and Gemini had comparable accuracy with correct response scores of 71% and 70.5%, respectively. Their performance varied across different sections. Gemini performed better in General Microbiology and Immunology, and ChatGPT 3.5 had a better score in the Applied Microbiology section. The study's findings highlight that AI platforms such as ChatGPT and Gemini can be utilized in microbiology and medical education. The evolution and continuous updating of AI platforms are required to improve their performance.
RESUMO
Meningoencephalitis refers to inflammation of the brain and meninges. It can be caused by various organisms, such as Neisseria meningitidis, Streptococcus pneumoniae, and so on. Staphylococcus aureus causing meningoencephalitis is relatively rare. It is mainly encountered in patients who have undergone surgeries in the past. Acute leukoencephalopathy with restricted diffusion (ALERD) is a type of encephalopathy that can involve both white and grey matter of the brain, and it has a characteristic "bright tree appearance" on MRI. It can be because of various infectious etiologies or caused by various toxins. Neurological sequelae are observed in about two out of three cases. Here, we describe a case of S. aureus meningoencephalitis with ALERD, which has been seldom reported. More awareness about this is required among primary care physicians for timely diagnosis and management to prevent any complications.
RESUMO
Introduction The COVID-19 pandemic has shaken the entire world ever since its emergence in March 2020. The disease manifestation of COVID-19 has been more severe, with a high degree of mortality in the elderly than in the young population. The cycle threshold (Ct ) value obtained in the real-time polymerase chain reaction (RT-PCR) has been used as the surrogate marker of viral load. Therefore, assessing Ct value and clinical status among different age groups with SARS-CoV-2 infection is required to understand the viral kinetics and to assess the transmission potential of that particular age group. Purpose The aim of this study was to compare the viral load and clinical status among different age groups with COVID-19 infection. Methods and materials A retrospective cross-sectional study was carried out to analyze the Ct values of SARS-CoV-2 positive samples reported from April 2020 till May 2021. The results of 13,820 RT-PCR (reverse transcriptase-polymerase chain reaction) positive samples were included for analysis of Ct values. Ct values of confirmatory genes were taken into consideration, and Ct values below 25, >25 to 30, and >30 were categorized as high, moderate, and low viral load, respectively. Age group was stratified into ≤18 years (young), 18-60 years (adult), and >60 years (elderly). The data were analyzed using SPSS Windows Version 25.0. Results The mean Ct values were 27.9, 26, and 26.2 in the young, adult, and elderly age groups, respectively. The mean Ct values of young patients were significantly higher as compared to adult and elderly patients (p<0.05). The percentage of high viral load (Ct<25) was found to be significantly higher in adults and elderly (44.6% & 43.7%) as compared to young (32.2%) (p<0.001). Majority of the COVID-19 positive cases younger than 18 years (75.9%) were asymptomatic as compared to 64.5% and 59.7% in the adult and elderly age groups, respectively. Conclusion This study observed a significantly high proportion of viral load in the adult and elderly population, which plays a substantial contribution to SARS-CoV-2 transmission, whereas the majority of the young population being asymptomatic plays a major role as silent transmitters. The study reemphasizes the need for strict adherence to COVID-appropriate behaviors.
RESUMO
Cystoisospora belli is an obligate intracellular coccidian parasite known to cause chronic persistent diarrhoea in immunocompromised individuals such as human immunodeficiency virus (HIV) infection, long term corticosteroid therapy, cancer chemotherapy and solid organ transplant recipients. Trichuris trichiura is a soil transmitted helminth, which predominantly causes asymptomatic or mild infections but heavy worm load can sometimes lead to chronic diarrhoea, tenesmus or rectal prolapse. We report a case of co-infection with Cystoisospora belli and Trichuris trichiura in an adult patient causing intractable diarrhea, which led to the unraveling of a severely compromised immune status in the patient enabling an appropriate therapeutic approach and further management.
Assuntos
Coinfecção , Infecções por HIV , Adulto , Animais , Coinfecção/complicações , Diarreia/parasitologia , Infecções por HIV/complicações , Humanos , Hospedeiro Imunocomprometido , TrichurisRESUMO
COVID-19 pandemic is a cause of global concern and is impacting lives and economy globally. Infection due to SARS-CoV-2 leads to varied clinical manifestations, which can vary from asymptomatic to severe acute respiratory syndrome and death. The clinical features are proposed to depend upon various host factors, namely, gender and genetic factors. The significantly high mortality among males has revealed the role of gender, androgens, age, genetics, and risk factors in determining the severity of COVID-19 among the population. The interplay of various host factors and their association with clinically severe infections is crucial for our understanding of COVID-19 pathogenesis. A PubMed and Google scholar search was made using keywords such as "COVID-19 + sex differences," "COVID-19 + androgens," "COVID-19 + ACE2 receptor," and "COVID-19 + smoking alcoholism pregnancy." The articles which highlight the association of gender and genetic factors to COVID-19 were selected and included in our study. It is mainly the primary care or family physicians who act as the first contact of COVID-19 patients. With the recent increase in SARS-CoV-2 infections in the Indian subcontinent and probability of upcoming surges, it has become imperative to understand its interaction with the various gender and genetic factors to devise effective triage and management protocols. Our review highlights the possible mechanisms by which these factors impact the severity of COVID-19. A better understanding of these factors will be of immense help to primary care physicians.
RESUMO
The aim of this article was to study the spectrum of scrub typhus meningitis/meningoencephalitis (STM) cases in children. Children ≤14 years of age with acute undifferentiated febrile illness were included. Immunoglobulin M (IgM) enzyme-linked immunosorbent assay was done in blood and cerebrospinal fluid (CSF) of children with suspected STM. Demographic, clinical, and laboratory details were expressed as descriptive statistics. Factors associated with neurological involvement were identified on univariate analysis. A total of 76 children had ST during the study period (meningitis/meningoencephalitis = 8 [10.5%], of which 5 [62.5%] had detectable ST IgM antibodies in CSF). The included children were 4 to 12 years of age with boys > girls. Headache and vomiting were common in those with STM, whereas hyponatremia and thrombocytopenia were common in those without STM. All children with STM recovered with sequelae in one child (right lateral rectus palsy). There was no mortality. STM has an incidence of 10.5% in children with ST from Eastern India. Headache and vomiting were significant predictors of STM, whereas hyponatremia and thrombocytopenia were significant predictor of non-STM.
RESUMO
BACKGROUND: Recently, a novel species contaminans belonging to the family Burkholderia cepacia complex (Bcc) is rising as a hospital pathogen. Detection of Burkholderia contaminans, a member of Bcc can be done only by MALDI TOF and sequencing techniques. We report the diagnostic challenges faced in an outbreak of bacteremia due to B. contaminans grown in diltiazem vials. METHOD: The department of microbiology notified the infection control team about a cluster of eleven patients with B. contaminans isolated from blood culture. An outbreak investigation was initiated by performing environmental surveillance and sterility testing of solutions given for the patients. Routine phenotypical methods for identification of species followed by MALDI-TOF and sequencing was performed to identify the pathogen. RESULTS: All the patients detected with B. contaminans were having cardiac disease and received diltiazem. Sterility testing of diltiazem vials given for the patient and an unopened vial of same batch has grown B. contaminans. Clonal typing has confirmed the sequence similarities between patient and solution isolates. CONCLUSION: Due to diagnostic challenge in identifying the species of Bcc, MALDI TOF and clonal typing remains the key diagnostic tools available to detect Bcc species at an earliest especially in an outbreak.
Assuntos
Infecções por Burkholderia , Burkholderia , Contaminação de Medicamentos , Hemocultura , Infecções por Burkholderia/diagnóstico , Infecções por Burkholderia/epidemiologia , Complexo Burkholderia cepacia , Diltiazem , Surtos de Doenças , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Centros de Atenção TerciáriaRESUMO
Introduction: Confirmatory diagnosis of hepatitis C virus (HCV) infection (HCV RNA detection) is essential before start of the therapy. HCV RNA detection is not available in many parts of India. Shipment of plasma from distant places to referral laboratories may affect HCV RNA titres. Dried blood spots (DBS) provide an easy alternative for transporting samples to centres where HCV RNA testing is done. Aim: Evaluation of DBS as a feasible alternative to plasma for HCV diagnosis. Methods: In this cross-sectional study, 40 consecutive patients' blood samples were collected from patients referred from the Liver Clinic. Whole blood was spotted onto two Whatman 903TM cards. One card was incubated at ≥37°C and other at 4°C for 15 days, after drying. DBS was eluted and run in Abbott RealTime HCV assay. HCV was also quantified using the Abbott ARCHITECT HCV core antigen assay for 29 of the study patients. Results were compared with normal plasma values. Results: The median log HCV RNA value (in log10IU/mL) of plasma was 5.74, with normalised DBS it was 4.92 (≥37°C) and 4.66 (4°C); difference in plasma and DBS median log values was 0.82 (≥37°C) and 1.08 (4°C) logs, respectively. Interclass correlation values were 0.943, P < 0.0001 (≥37°C) and 0.950, P < 0.0001 (4°C), showing high agreement. The median HCV core antigen value (in fmol/L) for plasma was 325.35, whereas it was 4.77 (≥37°C) and 4.64 (4°C) for DBS samples. Conclusions: DBS can be used for sampling patients from distant resource-limited settings as an alternative to plasma for HCV RNA estimation. Larger studies are required to evaluate the feasibility of DBS in the Indian subcontinent, especially for HCV core antigen estimation.
Assuntos
Teste em Amostras de Sangue Seco , Hepacivirus/isolamento & purificação , Hepatite C/diagnóstico , RNA Viral/sangue , Adulto , Estudos Transversais , Hepacivirus/genética , Hepatite C/virologia , Humanos , Pessoa de Meia-Idade , Projetos Piloto , Sensibilidade e Especificidade , Manejo de Espécimes/métodosRESUMO
Scrub typhus is a mite borne infectious disease which has re-emerged in India in the 3rd millennium after years of quiescence. In this review, the authors hypothesize the various factors responsible for resurgence of this disease. The main drivers that could have contributed to the upsurge in scrub typhus cases in past two decades are changes in land use land cover (LULC) and urbanisation which are; as a result of the population explosion, causing a strain on sanitation and also increased diversion of forest land for agricultural use. In addition, the availability of better tests, changes in antimicrobial use, climate change also could have impacted the epidemiology, which is showing an upward trend as is evidenced by increasing reports and concomitant publications from India on scrub typhus. Scrub typhus cases are supposed to increase in the coming years as factors like global warming, urbanisation, changes in LULC and rise in AMR (anti-microbial resistance) will be difficult or impossible to control. Therefore, increasing awareness of public and health care professionals regarding scrub typhus coupled with availability of rapid diagnostic assays and implementation of appropriate treatment protocols for control of AFI (acute febrile illness) especially at the community level will help mitigate the scenario in the long run.