The baseline widal titre among the healthy individuals of the hilly areas in the garhwal region of uttarakhand, India

Estimation of Baseline Widal Antibody Titers among Apparently Healthy Urban Population of District Jammu

Introduction:

Definitive diagnosis of Enteric fever is by blood culture for Salmonella enterica serotype Typhi, Paratyphi A, and Paratyphi B which takes long turnaround time and is costly, whereas Widal test is simple, rapid, and cost-effective test whose interpretation depends on the baseline Widal titers among healthy individuals in a defined population.

Objectives:

To determine the baseline Widal titers among apparently healthy urban population of district Jammu (J&K).

Materials and Methods:

302 individuals in the age group of 18–50 years were recruited. A pretested questionnaire was used to collect demographic and clinical details. The Widal testing was done using commercial Salmonella antigen kit.

Results:

A total of 302 samples were screened by Widal test. 138 samples (45.69%) were reactive for TO antigen and 64 (21.19%) tested reactive for TH antigen, 3 (0.01%) samples showed agglutination for AH antigen and 3 (0.01%) were positive for BH antigen. Majority of seropositive samples were in dilutions of 1:40 for both TO and TH antigens.

Conclusions:

Hence, next higher dilutions showing positivity for both TO and TH antigens, i.e., ≥1:80 may be considered diagnostic for enteric fever in the urban population of Jammu district.

Hemophagocytic lymphohistiocytosis as a diagnostic consideration of fever of unknown origin with pancytopenia and chronic liver disease

Hemophagocytic lymphohistiocytosis (HLH) is a severe disorder of systemic immune dysregulation which can be primary or secondary to autoimmune disorders, malignancy, or infections. We hereby describe a case of a 23-year-old male with severe hepatitis along with pancytopenia and prolonged fever of unknown origin that developed HLH triggered by staphylococcal urinary tract infection. This is a discussion of this unusual disease and its presentation and the diagnostic difficulties which may be encountered in general clinical practice.

Baseline Antibody Titre against Salmonella enterica in Healthy Population of Mumbai, Maharashtra, India

Objective

The aim of this study was to establish a baseline titre for the population of Mumbai, Maharashtra, India.

Method

Four hundred healthy blood donors, attending blood donation camps, were screened using a survey questionnaire. Widal tube agglutination test was performed on the diluted sera (with 0.9% normal saline) of blood donors, with final dilution ranging from 1 : 40 to 1 : 320.

Results

Out of 400 individuals providing samples, 78 (19.5%) individuals showed antibody titres ≥ 1 : 40 for at least one antigen and 322 (80.5%) showed no agglutination. The baseline antibody titres against O antigen and H antigen of Salmonella enterica serotype Typhi were found to be 1 : 40 and 1 : 80, respectively. Similarly, the baseline antibody titres for the H antigen of Salmonella enterica serotypes Paratyphi A and Paratyphi B were found to be 1 : 40 and 1 : 80, respectively.

Conclusion

Thus, it was noted that the diagnostically significant cutoff of antibody titre from acute phase sample was ≥ 1 : 80 for S. Typhi O antigen and titre of ≥ 1 : 160 for both S. Typhi H antigen and S. Paratyphi BH antigen. Antibody titre of ≥ 1 : 80 can be considered significant for S. Paratyphi AH antigen.

Retrospective audit of the widal test for diagnosis of typhoid Fever in pediatric patients in an endemic region

INTRODUCTION

Although typhoid fever is confirmed by culture of Salmonella Typhi, Widal test is widely used in India but little information exists about its reliability.

MATERIALS AND METHODS

We examined the performance of Widal test in our hospital for diagnosis of typhoid fever in children. Hundred consecutive pediatric in-patients for whom, the Widal test was requested were grouped into four categories: widal positive and clinically consistent with typhoid fever (Group 1; n=42), widal negative but clinically consistent (Group 2, n=12), widal positive but not clinically consistent (Group 3, n=12) and widal negative and also not clinically consistent (Group 4, n=34). The results were analyzed by the test performance criteria, namely, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) using culture-confirmed typhoid fever cases as the "true positives".

RESULTS

We found that 7/100 patients had culture-proven typhoid fever. Using a cut off ≥ 50 for O agglutinins or ≥100 for H agglutinins, the Widal test gave a sensitivity of 71.43%, specificity of 47.31%, and a positive predictive value of 09.25% and a negative predictive value of 95.65%.

CONCLUSION

The Widal test is an easy, inexpensive and relatively non-invasive but is not reliable in our set up because of a low PPV. There is a need for a more efficient rapid diagnostic test for typhoid fever.

Determination of baseline widal titres amongst apparently healthy blood donors in ahmednagar, maharashtra, India

BACKGROUND

Enteric fever is endemic in all parts of India. The Widal agglutination test is widely used for its diagnosis. But the interpretation of Widal test depends upon the baseline titre which is prevalent amongst healthy individuals in a particular geographical area.

AIM

Present study was undertaken to establish the normal baseline titre in apparently healthy blood donors and also to determine cutoff values for the Widal test.

MATERIAL AND METHODS

One hundred and three (103) sera were tested by the Widal tube agglutination test from January 2012 to February 2013.

RESULTS

Eighty four (81.55%) sera were positive for agglutinins (titre ≥ 1:20) and the remaining 19 were negative. 31.64% sera were positive for agglutinins of 'O' antigen of Salmonella typhi (TO) at a titre of 1:40, 33.87% sera were positive for 'H' antigen of Salmonella typhi (TH) at a titre of 1:40 and 38.46% and 36.84% sera were positive for 'H' antigen of Salmonella paratyphi A (AH) and Salmonella paratyphi B (BH) respectively, both at a titre of 1:80.

CONCLUSION

Therefore, the baseline titre for TO and TH was noted to be 1:40 and that for AH and BH was noted to be 1:80 and therefore, the cutoff level for TO and TH was ≥ 1:80 and that for AH and BH was ≥ 1:160.