The accuracy of widal test for typhoid fever diagnosis in Ethiopia: Systematic review and meta-analysis

Introduction: Widal agglutination test is a serologic investigation that is used to diagnose typhoidfever. This is an easy, fairly inexpensive, and readily available test it'ith questionable reliability. The test performance differs from setting to setting depending on the technique used and otherfactors. The accuracy ofthis test in Ethiopia is poorly understood. So, the aim of this scientific work was to analyze the accuracy of Widal agglutination in diagnosing typhoidfever in Ethiopia. Methods: We performed a systematic review and meta-analysis. Two electronic databases (PubMed/Medline and Google scholar) were searched using preset search strategv to find relevant studies. The methodological quality of the studies included was evaluated "'ith a QUADAS-2. We extracted important variables from the eligible articles. Statistical analysis was conducted using STATA version 14. The protocol of our systematic review and metaanalysis is registered in the International Prospective Register of Systematic Reviews (PROSPERO) with the record number CRD42020194252. Results: The electronic quests yielded 42 papers of which 8 "'ere eligible for analysis. The quality of these studies was rated to be moderate based on the QUADAS-2. The pooled sensitivity, specificity, and negative, andpositive predicthe values ofthe Widal test were 80.8%, 53.0%, 98.5%, and 2.1% respecth'ely. Conclusion: The "'idal agglutination test has average specificity, ven good negative predicth'e value, and ven poor positive predictive value for the diagnosis of typhoidfever. Depending on Widal to diagnose typhoid fever may lead to over-diagnosis of typhoid fever and related complications including inappropriate use of antibiotics. There is an urgent needfor quick and dependable tests for diagnosing typhoidfever, particularly in settings like Ethiopia M'here doing timely culture is notfeasible.

Analysis of predictors in outcome of fever with thrombocytopenia of pediatric age upto 12 years

Background: It is well recognized that many fetomaternal and neonatal conditions are associated with thrombocytopenia. Study aimed to establish the possible etiology of children presenting with thrombocytopenia.Methods: The study was carried out in 100 children 1 month-12 years, admitted at department of paediatrics, Narayana Medical College and Hospital, Nellore, Andhra Pradesh, India with fever and thrombocytopenia. A thorough history was obtained and a general and systemic examination done. Routine investigations were done in all cases and specific investigations as and when required.Results: Total 100 cases were studied. Among them, 65% developed only fever, 10% developed fever with bleeding and 25% developed fever with shock. In total admissions 55% of children admitted with warning symptoms including abdominal pain, vomiting, reduced urine output and black colored stools. There is a significant influence of warning symptoms in predicting the outcome of fever with thrombocytopenia. 30% of children admitted with respiratory distress. 30% of children admitted with abdominal distension. 60% children admitted with hepatomegaly. In these children, 20% of them developed fever with shock and 13% of them developed fever with bleeding, 52% children admitted with platelet count less than 1 lakh. In these patients, 19% of them developed fever with shock and 9% of them developed fever with bleeding. 60% had dengue serology positive, 12% had positive Widal test, 8% children had positive urine culture and sensitivity. There was a significant influence of etiology in predicting the morbidity as 15% of children having positive serology for dengue developed fever with shock. 10% of children having positive serology for dengue developed fever with bleeding. Bleeding manifestations were seen most commonly in children with a platelet count less than 50000/?l.Conclusions: The commonest cause of febrile thrombocytopenia in this study was dengue fever in Children. Platelet count was the predictive of bleeding manifestations.

A comparative study of Widal test and Typhidot (IgM and IgG specific assay) test in the diagnosis of enteric fever

Background: Enteric fever (Typhoid fever) is a common systemic infectious disease worldwide, especially in developing countries like India and continues to be one of the leading causes of morbidity and mortality. It is caused by the bacterium Salmonella typhi or Salmonella paratyphi serotypes A, B and C. The clinical diagnosis of Enteric fever traditionally depends on Blood culture and Widal tests. However limitations such as longer time for Blood culture results and difficulties in the interpretation of Widal tests make them unpractical for screening patients in endemic regions and lead to misdiagnosis and missed diagnosis. Aim and objectives: Purpose of the study was to compare the sensitivity and specificity of Widal test and Typhidot based IgM and IgG assay with the Blood culture (taken as gold standard) in the diagnosis of Enteric fever. Materials and methods: This comparative study was done on 120 patients in the General Medicine Department of Indira Gandhi Institute of Medical Sciences, Patna. All patients above 11 years of age of either sex with acute febrile illness suspected to have Enteric fever were included in this study. Febrile patients with other diagnosis were excluded. Blood culture, Widal test, Typhidot (IgM and IgG) test and other routine investigations were performed in all patients. Typhidot tests and Widal tests were compared for sensitivity and specificity. Results: Out of 120 clinically diagnosed cases of Enteric fever, 18(15%) patients were Blood culture positive for Salmonella typhi, 27(22.5%) patients were positive on Widal tests and 36(30%) were Typhidot positive. Out of 18 Blood culture positive patients for Salmonella typhi, 10 patients were Jyoti Kumar Dinkar, Naresh Kumar, Chandrakishore. A comparative study of Widal test and Typhidot (IgM and IgG specific assay) test in the diagnosis of enteric fever. IAIM, 2017; 4(7): 126-130. Page 127 positive and 8 were negative on Widal testing. Out of 36 Typhidot positive patients 16 patients were positive and 20 were negative on Blood culture. Conclusions: Traditionally Blood culture and Widal test are used in the diagnosis of Enteric fever. However Typhidot (IgM & IgG assay) tests are simple and rapid screening tests that simultaneously detect and differentiate between IgM and IgG antibody to Salmonella typhi and paratyphi produced in response to infection, thus aiding in determination of current or previous exposure. It offers the advantage of early and rapid diagnosis and helps in early institution of therapy. Preliminary data have shown sensitivity and specificity of 95% and 86% respectively of Typhidot tests.

A Prospective Comparative Study of Semi-Quantitative Slide Widal test& Quantitative Tube Widal test.

Objective: The diagnosis of enteric fever currently depends upon the isolation of Salmonella from a patient, most commonly by blood culture. This facility is not available in many areas where the disease is endemic. The Widal agglutination test which demonstrates the presence of somatic (O) and flagellar (H) agglutinins to Salmonella in the patient's serum using O and H antigen suspension is one of the most utilized diagnostic tests for typhoid fever in developing countries. In the recent past, a rapid slide test was developed which is now the most commonly used technique in local laboratories because of its convenience. The semi-quantitative slide test provides an approximation to the tube test titre. The present study was an attempt to compare the results of semi-quantitative slide agglutination with the quantitative tube method to ascertain any significant difference between two methods. Material and Methods: 300 precollected blood samples of OPD patients were collected over a period of 4 months and subjected to semi-quantitative rapid slide and quantitative tube Widal tests using commercially available Salmonella antigen test kits. Results: From the 300 samples studied, 17(5.7%) serum samples were positive by slide test method while 25(8.7%) seropositive by Tube test method. Present study shows, slight difference in the results obtained by the two methods of Widal test. Conclusion: The Tube Widal test is more sensitive and specific than slide Widal test, especially for rule out prozone phenomena, but slide Widal agglutination test is found to good alternative screening test because less time consuming, easy to perform, cost effective and can be applied in resource poor nations. There is an urgent need for the rational design and evaluation of effective and appropriate diagnostics for typhoid fever.

A Prevalence Study of Typhoid Fever in Taiz and Al-Hodiedah cities in Yemen.

Aims: Typhoid fever is an acute illness associated with fever that is most often caused by the Salmonella typhi bacteria. This study was carried out to determine the prevalenece of typhoid fever and distribution among different groups in Al-hodiedah and Taiz hospitals, and to determine the relation between the two governorates. Study Design: Seroprevalence survey. Place and Duration of Study: This study was carried out in Taiz hospitals and Al- Hodiedah hospitals in Yemen for about 1500 cases during September to December 2012. Methodology: A total of 1500 cases were randomly collected and examined by Widal test and blood samples for WBC to detect the typhoid fever. Also, the questionnaire data was used for determine the correlation between typhoid fever and other factors such as age, sex, and clinical symptoms, then the data analyzed by spss program. Results: This study found that 151 cases of typhoid fever are positive for widal test from total 1500 specimens was collected from Al-hodiedah hospitals and Taiz hospitals. Also found from 151 positive cases 57 cases for male and 94 cases for female. There were 55 cases the main complain was fever follow by diarrhea 42 cases then abdominal pain 31 cases. Conclusion: The results of the study indicate that there is no significant different in the prevalence of typhoid fever between cases collected from Taizhospitals and Al-Hodeida hospitals. Also, no significant different between sex or age and the positive cases. The positive cases were come with different manifestations such as fever, abdominal pain and diarrhea.

Typhidot M and Diazo test vis-à-vis blood culture and Widal test in the early diagnosis of typhoid fever in children in a resource poor setting

OBJECTIVE: Typhoid fever is a major public health problem. A test which is simple, reliable and can be carried out in small laboratories is the need of the hour. We prospectively evaluated typhidot M and Diazo tests vis-à-vis blood culture and Widal test in children. METHODS: Patients aged 6 months to 12 years, having fever of more than four days duration with clinical suspicion of typhoid fever were enrolled. Patients in whom other diagnosis was made served as control. The tests under scrutiny were validated against blood culture and then all the four tests were evaluated among patients who presented in the first week of illness. RESULTS: Blood culture was positive in only 27.3 percent of the cases. Among these culture positive cases, typhidot M test had the highest sensitivity, specificity, PPV and NPV of 90 percent (95 percent CI = 74.4-96.5), 100 percent (95 percent CI = 90.1-100), 100 percent (95 percent CI = 87.5-100), and 92.1 percent (95 percent CI = 79.2-97.3) respectively. Diazo test ranked next with sensitivity, specificity, PPV and NPV of 86.7 percent (95 percent CI = 70.3-94.7), 85.7 percent (95 percent CI = 70.6-93.7), 83.9 percent (95 percent CI = 67.4-92.9), 88.2 percent (95 percent CI = 73.4-95.3) respectively. Among clinically suspected typhoid cases, the overall sensitivity, of blood culture, Widal, typhidot M, Diazo was 27.3 percent (95 percent CI = 19.8- 36.3), 64.6 percent (95 percent CI = 55.3-72.9), 89.1 percent (95 percent CI = 81.9-93.7), 80.9 percent (95 percent CI = 72.6-87.2) respectively. In the first week of illness, typhidot M showed the best sensitivity [86.2 percent (95 percent CI = 69.4-94.5)] followed by Diazo [79 percent (95 percent CI = 61.6-90.2)], Widal [41.4 percent (95 percent CI = 25.5-59.3)] and blood culture [31 percent (95 percent CI = 17.3-49.2)]. CONCLUSION: Both Typhidot M and Diazo are good screening tests for the diagnosis of typhoid fever. Typhidot M is superior to Diazo but the latter is more suitable to resource poor settings being economic and easy to perform.

Comparative Study of Dot Enzyme Immunoassay (Typhidot-M) and Widal Test in the Diagnosis of Typhoid Fever.

We compared the sensitivity and specificity of Typhidot-M and Widal test with blood culture (gold standard) for diagnosing typhoid fever in 105 children aged 1-15 years admitted with clinical suspicion of typhoid fever. Of the 105 cases, blood culture was positive for S.typhi in 41 (39%) children, Widal test was positive in 48 (45.7%) and Typhidot-M was positive in 78 (74.3%) cases. Sensitivity and specificity of Typhidot-M was 92.6% and 37.5% while sensitivity and specificity of Widal test was 34.1% and 42.8%, respectively. In children with fever of less than 7 days duration, Typhidot-M was positive in 97%, compared to 24.2% by Widal test. Typhidot-M is a simple and sensitive test for early diagnosis of typhoid fever in children.

Evaluation of a Rapid Immunochromatographic Assay Kit for the Diagnosis of Salmonella Typhi Infection / 대한임상미생물학회지

BACKGROUND: Widal test, whose sensitivity and specificity are variable from region to region depending on the incidence of typhoid fever, is still in use and shows a relatively low positive predictive value in Korea. We evaluated a rapid immunochromatographic assay (ICA) kit for the rapid diagnosis of Salmonella Typhi infection. METHODS: Twenty five patients with Salmonella Typhi bacteremia were selected for the patient group. For the control group, 21 nontyphoidal salmonellosis patients, 56 non-Salmonella bacteremia patients, and 57 healthy individuals were selected for evaluating the specificity of ICA test. Each serum specimen was tested with the SD Salmonella Typhi IgG/IgM kits (Standard Diagnostics, Inc., Yongin, Korea). RESULTS: The ICA showed a sensitivity of 100% in Salmonella Typhi patients, and specificities of 61.9%, 82.1% and 91.2% in nontyphoidal salmonellosis patients, non-Salmonella bacteremia patients, and healthy individuals, respectively. The ICA test showed a high sensitivity but a low specificity when compared with the Widal test. CONCLUSION: The ICA test by SD Salmonella Typhi IgG/IgM kit is highly sensitive, but its specificity is relatively low. The ICA test is simple, objective, and suitable for screening typhoid fever.

Hemocultivo, Coprocultivo y Reacción de Widal en la detección de Salmonella Entérica en pacientes con Salmonelosis / The use of blood culture, stool culture and Widal test in the detection of Enteric Salmonella in patients with Salmonellosis

Tipo de estudio: Transversal descriptivo.Objetivos: Identificar el agente etiológico por cultivo en sangre y heces a los pacientes con cuadro clínico sospechoso de salmonelosis, y analizar el verdadero valor de la prueba reacción de Widal de la que se ha hecho un uso indiscriminado.Materiales y Métodos: Se estudiaron 59 pacientes que acudieron a Emergencia del hospital de Infectología “Dr. José Daniel Rodríguez Maridueña”, de ambos sexos, mayores de doce años, entre noviembre 2002 y mayo 2003. Se les realizó hemograma, reacción de Widal, hemocultivo y coprocultivo en el Instituto Nacional de Higiene y Medicina Tropical “Leopoldo Izquieta Pérez”.Resultados: Se aisló salmonela Typhi en el 3,8% de hemocultivos realizados a pacientes con RW positiva y sospecha de fiebre tifoidea; en el 21,7% de los pacientes que presentaban clínica más leucopenia y en el 25%, con clínica, leucopenia y RW positiva. Se aisló enterobacterias en el 12% de los pacientes con gastroenteritis; 5% salmonela no tifoideas grupo C, 5% E. Coli y, 2% shiguela.Conclusiones: Se confirmó que la RW no es concluyente en el diagnóstico de Fiebre Tifoidea, y que el cuadro clínico de gastroenteritis por salmonela es indiferenciable del ocasionado por otros agentes bacterianos o no.

Type of study: Transversal descriptive.Objectives: Identify the etiologic agent by blood and stool culture and analize the real value of Widal test.Materials and Methods: 59 patients with clinical features of salmonellosis that went to the emergency room of the Infectology Hospital José Daniel Rodriguez Maridueña of both sexs, older than twelve years old were studied between November 2002 and May 2003. Hemogram, Widal test, blood culture and stool culture were done to each one.Results: Typhoid salmonella was isolated in 3,8% of blood cultures of positive Widal test and suspected of having typhoid fever, in the 21.7% of patients with clinical symptoms and leukopenia and in the 25% of patients with clinical symptoms, leukopenia and positive Widal test. Enterobacterias were isolated in 12% of gastroenteritis patients; 5% group C no Typhi Salmonella, 5% E coli, and 2% shiguella.Conclusions: We confirmed that Widal Test is not conclusive in the typhoid fever diagnosis and that the clinical features of salmonella gastroenteritis is indistinguishable from those caused by other bacterial or not bacterial agents.

Usefulness of Widal Test in the Diagnosis of Typhoid Fever / 감염

BACKGROUND: Typhoid can be diagnosed with certainly only by the isolation of Salmonella Typhi from the blood, urine, feces, or other body fluids. The Widal reaction has been one of the most important diagnostic tests for typhoid and is still widely used in many developing countries. METHODS: The Widal test was done in 50 nontyphoidal febrile patients, and 50 patients with proven typhoid in Chonbuk area. we compare this result with that of last 10 years. RESULTS: By rapid slide method S. typhi O titer of 1:160 or more was seen in 58% and S. typhi H titer of 1:320 or more was seen in 12% of patients with bacteriologically proven typhoid fever. CONCLUSION: O titer was similar to the result of past 10 years. A false positive test was found in 40% of patients with nontyphoidal febrile patients in whom Widal test must therefore be interpreted with caution.

Is the Widal Test Still Useful? / 대한임상병리학회지

BACKGROUND: Widal test has been one of the most important diagnostic tests for typhoid and is still widely used. Widal test has been useful diagnostic tool for typhoid in endemic areas, while it has been largely abandoned in developed countries. Since 1990, occurrance of typhoid has been markedly decreased in Korea, we studied diagnostic usefulness and criteria of Widal test from 1990 to 1997. METHODS: Using rapid slide titration method (Stained Salmonella suspensions, Murex Biotech Ltd., Dartford, England), the Widal test was done in 116 nontyphoid salmonellosis patients, 75 patients with proven typhoid fever, and 173 cases of clinically suspected typhoid fever patients. Stastical analysis was done with discriminant analysis in culture proven salmonellosis. RESULTS: Fifty-four culture proven cases of Salmonella paratyphi (S. paratyphi) A and S. paratyphi B showed no significant cutoff value in O antibodies. Salmonella typhi (S. typhi) O titer at the 1:160 and above showed lower sensitivity (37.3% vs. 69.3%) and specificity (91.4% vs. 93.1%) compared to S. typhi H titer at the 1:320 and above in diagnosis of culture proven cases of typhoid. We applied D (0.01xH titer+0.001xO titer-1.635) score which result from discriminant analysis. Positive D score (> or =0.21) showed sensitivity of 72% and specificity of 92.2% in culture proven cases of typhoid. In clinically suspected patients, positive D score showed 39.3% of sensitivity. CONCLUSIONS: We concluded that the Widal test for O antibodies of S. paratyphi A and S. paratyphi B is not useful for diagnosis of paratyphoid fever. In the present study S. typhi H antibodies are more diagnostic than S. typhi O antibodies. We appled D score and positive D score showed increased sensitivity of Widal test than application of O antibody titer.