comparison of disease caused by Shigella and Campylobacter species: 24 months community based surveillance in 4 slums of Karachi, Pakistan

Despite the efforts of the international community diarrheal diseases still pose a major threat to children in children less than five years of age. Bacterial diarrhea has also emerged as a public health concern due to the proliferation of drug resistant species in many parts of the world. There is a paucity of population-based data about the incidence of shigellosis and Campylobacter infections in Pakistan. We report country specific results for Shigella diarrhea that were derived from a multicenter study conducted in six Asian countries. Disease surveillance was conducted over a 24 month period in urban slums of Karachi, Pakistan, a city with a population of 59,584. Cases were detected through passive detection in study treatment centers. Stool specimens or rectal swabs were collected from all consenting patients. Between January 2002 and December 2003 10,540 enteric infection cases were detected. The incidence rate of treated diarrhea in children under 5 was 488/1000/year. In children, 5 years and older, the diarrhea rate was 22/1000/year. 576 [7%] Campylobacter isolates were detected. The pre-dominant Campylobacter species was C. jenuni with an increase of 29/1000 year in children under 5 years. Shigella species were isolated from 394 of 8032 children under 5 years of age. Shigella flexneri was the dominant species [10/1000/year in children under 5 years] followed by Shigella sonnei [3.9/1000/year], Shigella boydii [2.0/1000/year] and Shigella dysenteriae [1.3/1000/year]. Shigellosis and Campylobacter infection rates peaked during the second year of life. The incidence rate of shigellosis increased in old age but such a trend was not observed in Campylobacter infections. Of 394 shigellosis patients 123 [31%] presented with dysentery in contrast to only 54 [9%] of 576 patients with Campylobacter infections [p < 0.001]. Both Campylobacter infections and shigellosis are common in community settings of Pakistan but shigellosis presented more frequently with abdominal pain and dysentery than Campylobacter infections indicating that shigellosis may be a more severe illness than Campylobacter infections. Due to the increased and disease severity, drug resistant shigella have become a significant health problem; moreover it is a disease of poor and impoverished people who do not have the access to standard water and sanitary conditions, health care services or optimal treatment. In the face of these facts it is empirically important to develop a low cost effective vaccine that can protect these populations for a longer duration

Effect of zinc in tablet and suspension formulations in the treatment of acute diarrhoea among young children in an emergency setting of earthquake affected region of Pakistan

A longitudinal cohort study was conducted at Camp Hospital Batagram in August 2006 to ascertain the effect of Zinc utilization in tablet and suspension formulations on thr frequency and recovery rates of diarrhoea among young children in the emergency settings of earthquake affected region of Pakistan. Two hundred patients were recruited and followed-up, the patients were allocated either of the 2 groups i.e. A [Zinc in tablets form] and B [Zinc in suspension form]. Both groups also received WHO recommended treatment for diarrhoea. Most of the cases recovered from the illness within 3 days after presentation. Significant p-values were established among Zinc use and reduction in frequency of stools on Day 2 and 3, with better outcome in group B. The study supports the notion that Zinc reduces the frequency and improves recovery rates of diarrhoea in any form and has better compliance and outcomes with the use in suspension form

Health care utilization for diarrhea and fever in 4 urban slums in Karachi

To estimate the fraction of fever and diarrhea patients making use of private practitioners, self-treatment, hospital care, drug vendors, community health centers and traditional healers. A cross-sectional survey. Four slums in and around Karachi during October and November, 2001. A sample of 1842 households was selected with probability proportional to size of the slum. The household head or a representative was asked regarding the treatment providers for diarrhea and cases of fever persistent for 3 days or more. Only households with an actual case of fever and/or diarrhea were included in the analysis. The study found that more than half of diarrhea and fever cases are seen by private practitioners. Self medication with medicines available in the home or specifically purchased for the disease episode from a drug vendor combined provides 13% to 18% of health care. Only between 11% and 13% of patients are seen by the public sector, hospitals and community health centers. There was no significant difference between the choice of health care provider for diarrhea and fever cases. In this survey, the majority of fever and diarrhea patients presented first to private practitioners and not to drug vendors or the public sector. Successful passive surveillance of febrile or diarrheal illness in these communities has to integrate private practitioners

Frequency of isolation of Shigella Serogroups/Serotypes and their antimicrobial susceptibility pattern in children from slum areas in Karachi

To assess the frequency of serogroups and serotypes, as well as the antimicrobial susceptibility pattern of Shigella species isolated from known cases of diarrhoea and dysentery from Karachi, Pakistan. A cross-sectional study was conducted between January 2002 and March 2003 at Aga Khan University on stool samples received from children with diarrhoea and dysentery from four low socio-economic areas [Sultanabad, Rehri Goth, Hijrat and Sherpao colony] of Karachi. Stool samples yielding growth of Shigella species, were further identified for serotypes by slide agglutination. Antibiotics susceptibility was performed by Kirby Bauer disk diffusion method. Out of 4688 stool samples received, 193 [4.1%] were positive for Shigella species. Shigella flexneri was the predominant serogroup [58%] followed by Shigella sonnei [16%], Shigella boydii [15%] and Shigella dysentriae being the least common [11%]. A number of serotypes were isolated in each serogroup, 8 serotypes in S. flexneri, 8 serotypes in S. dysenteriae, 9 serotypes in S. boydii, and Phase 1 and 2 were found in S. sonnei. 17% isolates remained non-serotypeable. All isolates were susceptible to Ofloxacin and Ceftriaxone, high rate of resistance was observed in Cotrimoxazole [87.75%] and Ampicillin [55.5%]. Emerging resistance against Nalidixic acid [39%] was observed. Shigella still accounts for a significant proportion of bacillary dysentery in many tropical and subtropical countries. Serotype identification can help in devising strategies such as development of effective vaccine for controlling this problem. Increasing antibiotic resistance against commonly prescribed drugs signify that treatment options have become difficult in cases of severe dysentery [JPMA 55:184;2005]

review of Rotavirus Diarrhhea in Pakistan How much do we know?

Rotavirus diarrhea has a worldwide distribution, infecting almost all children by the age of 3-5 years. Epidemiology: A comparable etiological 2-year survey carried out by the W.H.O Diarrheal Disease control [CDD] Program in 1991, in a multicenter study in 5 developing countries including Pakistan revealed that Rotavirus was found to be the most frequently detected pathogen in diarrheal episodes, during the first year of life, with the highest incidence [20%] occurring among 6-11 months old. Two other studies done in Pakistan, in under five children done in Lahore [between 1985 and 1991] and Rawalpindi [between May 1983 and April 1984] showed that Rotavirus was the second most common Diarrhea causing enteric pathogen following E.Coli Transmission: Rotaviruses are shed in high concentrations 2 days before and as many as 10 days after onset of symptoms in immunocompetent hosts, thus being an important source of viral transmission1. Clinical Course: A multicenter study in 5 developing countries including Pakistan conducted by WHO CDD program revealed that only 1.8% of cases presented with severe dehydration and these were mostly due to Rotavirus, V.Cholerae and ETEC13. Diagnostic Tests: A study conducted in local hospitals in Pakistan during the period of October 1985-April 1986 compared the different diagnostic modalities for the detection of rotavirus in the faeces of children with acute diarrhea.2,3 The study all methods detected Rotavirus to varying degrees but ELISA was found to be the most sensitive method with 72.4% stools being positive. Preventive Strategies: A study was conducted in Lahore [Pakistan] among 72 infants 6 weeks old in 1991 to assess safety and efficacy of RRV vaccine. It was found that of all infants given RRV with OPV, 50% had a two to four-fold rise in neutralization titers against rotavirus. RRV was found to be safe and not associated with adverse reactions in the 6 weeks old infants. With regards to Pakistan, there is a great need for defining rotavirus associated disease burden and strain prevalence. We also need to conduct Rotavirus vaccine trials to assess its efficacy and safety in our setting

Assessment of zinc status in populations: some contemporary issues

Intense measures are needed to be undertaken to ensure accurate and precise assessment of zinc status when utilizing plasma/serum as an index. As larger population surveys of micronutrient status are undertaken, close attention to techniques and precautions in sample collection and analysis will ensure that the most accurate information is obtained. This is a review article

Epidemiology of neonatal sepsis in Pakistan: an analysis of available evidence and implications

It is recognized that nearly a half of all infant deaths in Pakistan occur within the neonatal period, but accurate information as to the attributable causes for this high mortality is lacking. In an effort to assess the spectrum and epidemiology of neonatal infections in Pakistan, we undertook a period analysis of all available reports on newborn infections and morbidity/mortality patterns over the last 30 years. The information available indicated that a large proportion, ranging from 50-88% of all neonatal deaths in several community-based surveys, were directly or indirectly attributable to infectious disorders. Among hospital-based reports, infections accounted for between 22-66% of all admissions to neonatal units, of which the most common were septicaemia and pneumonia. Although there was an apparent improvement over time, case-fatality rates with sepsis were high [41% overall]. The available information on causative organisms indicated that gram negative infections predominated with Klebsiella pneumoniae, Escherichia coli and Pseudomonas species accounting for over 60% of all isolates. There was a high incidence of multi-drug resistance among these isolates. The few studies identifying possible risk factors for infection by case-control techniques identified lack of attention to asepsis, low-birth-weight, birth asphyxia and failure to exclusively breastfeed as important contributory factors to neonatal sepsis. Our analysis highlights the importance of neonatal infections among newborn infants in Pakistan and the urgent need to institute preventive measures

Primary ciliary dyskinesia: a cause of neonatal respiratory distress

Primary ciliary dyskinesia [PCD] is a rare disorder associated with chronic respiratory problems and even more infrequently as a cause of neonatal respiratory distress. Of consecutive 12 children seen with a diagnosis of PCD, the disorder presented within the neonatal period in 11, with a positive family history in 50%. The diagnosis was delayed in several cases, despite suggestive radiological findings. The data highlights the importance of recognizing PCD in newborns presenting with early respiratory distress and isolated dextrocardia

Necrotizing enterocolitis in infants weighing 2000 g

Over a 4 year period, nine of 180 [5%] infants weighing less than 2000 G. admitted to the Aga Khan University Hospital [AKUH] developed necrotizing enterocolitis [NEC]. An outbreak of NEC occurred in 1989, during which six infants developed the clinical illness. Overall incidence was 1.1%. Thirty-one birth weight and gestation matched controls were selected for comparison. Risk factors usually considered as predisposing factors, i.e., low 5 min Apgar score, rate of maternal complications, respiratory distress syndrome, mechanical ventilation, umbilical catheterisation, patent ductus arteriosus, use of antibiotics and feeding practices were found with equal frequency in both cases and controls. Six infants had positive blood and/or peritoneal fluid cultures [66%] compared to only five [16%] in the control group [P < 0.01]. Our data suggests that prematurity and sepsis are important predisposing factors for development of NEC

Chloramphenicol therapy of typhoid fever

In a prospective study we compared two different dosage regimens of IV chloramphenicol succinate [100 mg/kg/day and 75 mg/kg/day] in children with culture proven typhoid. Trough and peak blood samples, obtained at 48 hrs, were analysed for free chloramphenicol by high pressure liquid chromatography [HPLC]. Although the mean trough [8.8 +/- 7.7 versus 5.4 +/- 2.6 mcg/ml] and peak [19.9 +/- 12.2 versus 15.4 +/- 6.1 mcg/ml] chloramphenicol concentrations were comparable in both groups, a significantly wider range was found in the group receiving 100 mg/kg/day. Potentially toxic levels [>30 mcg/ml] developed in two patients with liver dysfunction. Chloramphenicol in a dosage of 75 mg/kg/day is adequate and safe for the treatment of paediatric typhoid