14
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      True Prevalence of Shigellosis in Indian Children with Acute Gastroenteritis: Have We Been Missing the Diagnosis?

      research-article

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Background: Shigella is responsible for high morbidity and mortality among children, yet its true prevalence remains inconclusive. The aim of this study was to determine the actual prevalence of Shigella infection in childhood diarrhea and dysentery cases and assess the applicability of ipaH gene PCR in Indian settings.

          Methods: This study was conducted at Maulana Azad Medical College and associated Lok Nayak Hospital, New Delhi, India during 2011-12. A total of 385 children (207 with diarrhea, 118 with dysentery, and 60 matched controls) were enrolled. Stool samples were cultured, and the suspected colonies were analyzed using biochemical reactions and serotyping. Antimicrobial susceptibility testing was done using disc diffusion method. ipaH-gene PCR was performed directly on stool samples collected from 180 randomly selected patients (60 from each group).

          Results: Shigella was isolated using conventional culture methods in 8.2% (95% CI: 5.1%, 12.8%), 33.1% (95% CI: 25.2%, 42.0%), and 0% in the diarrhea, dysentery and control cases, respectively. High resistance was seen towards co-trimoxazole, nalidixic acid, fluoroquinolones, doxycycline and several beta-lactams drugs. Actual prevalence of shigellosis was determined using ipaH gene PCR to be 18.3% (95% CI: 10.4% – 30.1%) diarrhea cases and 56.7% (95% CI: 44.1, 68.4%) dysentery cases. One (1.7%, 95% CI: 0.01%, 9.7%) control specimen also yielded positive result in PCR.

          Conclusions: Correct diagnosis of shigellosis is essential to start antimicrobial therapy in selected cases. The prevalence of Shigella / EIEC infection in children is much higher than previously estimated. Despite its high costs and other limitations, we recommend the use of ipaH-gene PCR as a routine tool in the management of childhood acute gastroenteritis cases.

          Related collections

          Most cited references16

          • Record: found
          • Abstract: found
          • Article: not found

          Global burden of Shigella infections: implications for vaccine development and implementation of control strategies.

          Few studies provide data on the global morbidity and mortality caused by infection with Shigella spp.; such estimates are needed, however, to plan strategies of prevention and treatment. Here we report the results of a review of the literature published between 1966 and 1997 on Shigella infection. The data obtained permit calculation of the number of cases of Shigella infection and the associated mortality occurring worldwide each year, by age, and (as a proxy for disease severity) by clinical category, i.e. mild cases remaining at home, moderate cases requiring outpatient care, and severe cases demanding hospitalization. A sensitivity analysis was performed to estimate the high and low range of morbid and fatal cases in each category. Finally, the frequency distribution of Shigella infection, by serogroup and serotype and by region of the world, was determined. The annual number of Shigella episodes throughout the world was estimated to be 164.7 million, of which 163.2 million were in developing countries (with 1.1 million deaths) and 1.5 million in industrialized countries. A total of 69% of all episodes and 61% of all deaths attributable to shigellosis involved children under 5 years of age. The median percentages of isolates of S. flexneri, S. sonnei, S. boydii, and S. dysenteriae were, respectively, 60%, 15%, 6%, and 6% (30% of S. dysenteriae cases were type 1) in developing countries; and 16%, 77%, 2%, and 1% in industrialized countries. In developing countries, the predominant serotype of S. flexneri is 2a, followed by 1b, 3a, 4a, and 6. In industrialized countries, most isolates are S. flexneri 2a or other unspecified type 2 strains. Shigellosis, which continues to have an important global impact, cannot be adequately controlled with the existing prevention and treatment measures. Innovative strategies, including development of vaccines against the most common serotypes, could provide substantial benefits.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Detection of Shigella by a PCR assay targeting the ipaH gene suggests increased prevalence of shigellosis in Nha Trang, Vietnam.

            Shigella spp. are exquisitely fastidious gram-negative organisms which frequently escape detection by traditional culture methods. To get a more complete understanding of the disease burden caused by Shigella in Nha Trang, Vietnam, real-time PCR was used to detect Shigella DNA. Randomly selected rectal swab specimens from 60 Shigella culture-positive patients and 500 Shigella culture-negative patients detected by population-based surveillance of patients seeking care for diarrhea were processed by real-time PCR. The target of the primer pair is the invasion plasmid antigen H gene sequence (ipaH), carried by all four Shigella species and enteroinvasive Escherichia coli. Shigella spp. could be isolated from the rectal swabs of 547 of 19,206 (3%) patients with diarrhea. IpaH was detected in 55 of 60 (93%) Shigella culture-positive specimens, whereas it was detected in 87 of 245 (36%) culture-negative patients free of dysentery (P < 0.001). The number of PCR cycles required to detect a PCR product was highest for culture-negative, nonbloody diarrheal specimens (mean number of cycles to detection, 36.6) and was lowest for children with culture-positive, bloody diarrheal specimens (mean number of cycles, 25.3) (P < 0.001). The data from real-time PCR amplification indicate that the culture-proven prevalence of Shigella among patients with diarrhea may underestimate the prevalence of Shigella infections. The clinical presentation of shigellosis may be directly related to the bacterial load.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Quantitative PCR for detection of Shigella improves ascertainment of Shigella burden in children with moderate-to-severe diarrhea in low-income countries.

              Estimates of the prevalence of Shigella spp. are limited by the suboptimal sensitivity of current diagnostic and surveillance methods. We used a quantitative PCR (qPCR) assay to detect Shigella in the stool samples of 3,533 children aged 2.9 × 10(4) ipaH copies. Ninety (10%) specimens were positive by traditional culture for Shigella. Individuals with ≥ 2.9 × 10(4) ipaH copies have 5.6-times-higher odds of having diarrhea than those with <2.9 × 10(4) ipaH copies (95% confidence interval, 3.7 to 8.5; P < 0.0001). Nearly identical results were found using an independent set of samples. qPCR detected 155 additional MSD cases with high copy numbers of ipaH, a 90% increase from the 172 cases detected by culture in both samples. Among a subset (n = 2,874) comprising MSD cases and their age-, gender-, and location-matched controls, the fraction of MSD cases that were attributable to Shigella infection increased from 9.6% (n = 129) for culture to 17.6% (n = 262) for qPCR when employing our cutpoint. We suggest that qPCR with a cutpoint of approximately 1.4 × 10(4) ipaH copies be the new reference standard for the detection and diagnosis of shigellosis in children in low-income countries. The acceptance of this new standard would substantially increase the fraction of MSD cases that are attributable to Shigella.
                Bookmark

                Author and article information

                Journal
                J Res Health Sci
                J Res Health Sci
                J Res Health Sci
                J Res Health Sci
                JRHS
                Journal of Research in Health Sciences
                Hamadan University of Medical Sciences
                2228-7795
                2228-7809
                Winter 2016
                02 February 2016
                : 16
                : 1
                : 11-16
                Affiliations
                a Department of Microbiology, Maulana Azad Medical College, Bahadur Shah Zafar Road, New Delhi-110002, India
                b Department of Pediatrics, Maulana Azad Medical College and associated Lok Nayak Hospital, Bahadur Shah Zafar Road, New Delhi-110002, India
                Author notes
                [* ] Correspondence Prabhav Aggarwal (MD) Tel: +91 120 4347120 E-mail: prabhavaggarwal@ 123456yahoo.co.in
                Article
                7189089
                27061990
                41c99a3e-cbf5-4dfb-b26f-021ee28cd4c7
                © 2016 The Author(s); Published by Hamadan University of Medical Sciences.

                This is an open-access article distributed under the terms of the Creative Commons Attribution License ( http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

                History
                : 02 January 2016
                : 17 January 2016
                : 23 January 2016
                Page count
                Figures: 2, Tables: 2, References: 21, Pages: 6
                Categories
                Original Article

                shigella,diarrhea,dysentery,ipah,india
                shigella, diarrhea, dysentery, ipah, india

                Comments

                Comment on this article