Persistent diarrhoea in children in developing countries: Memorandum from a WHO Meeting

This Memorandum summarizes current knowledge of the epidemiology, etiology, and pathophysiology of persistent diarrhoea and describes current approaches to its management. A number of research topics are presented which focus especially on improving understanding of the causes of persistent diarrhoea and on developing more effective methods for treatment and prevention.     

Persistent diarrhoea in a rural area of Bangladesh: a community-based longitudinal study

As part of a health impact evaluation of a water supply and sanitation project in a rural area of Bangladesh, diarrhoeal morbidity was recorded in children 0-4 years of age using weekly recall in household interviews, during the period March 1984 to December 1987. During the baseline year, 1984, the incidence rate of all diarrhoea episodes (3.8 episodes per child per year), and those defined as persistent, duration greater than 14 days (0.6 episodes per child per year), showed a similar age distribution, peaking in the 12-23 month age group. Sixteen per cent of all episodes were classified as persistent, and this proportion was greatest in the 0-5 month age group (25%). Children suffering at least one episode of persistent diarrhoea in 1984 also experienced a higher incidence of acute diarrhoea (less than = 14 days duration) than those suffering acute diarrhoea only (4.2 versus 3.7 episodes per child per year). Persistent diarrhoea showed a similar seasonal pattern to that of all episodes. Rates of abdominal pain, isolation of Shigella spp and a diagnosis of dysentery were significantly higher in persistent episodes than in acute episodes. Closer follow-up of children during 1986 and 1987, through the recording of all periods of absence of the child from the home, showed that overall diarrhoea incidence rates were little affected when absence was taken into account, but that the incidence of persistent diarrhoea and the proportion of episodes classified as persistent were significantly reduced. The implications of this methodological problem are discussed.     

Persistent and acute diarrhoea as the leading causes of child mortality in urban Guinea Bissau.

An investigation of child mortality in a semi-urban community, Bandim II, in the capital of Guinea Bissau was carried out from April 1987 to March 1990. 153 deaths were recorded among 1426 live-born children who were followed for 2753 child-years. The under-five mortality risk was 215 per 1000 children (95% confidence interval [CI] 176-264), infant mortality 94 per 1000 (95% CI 73-115), and perinatal mortality 52 per 1000 (95% CI 41-63). By prospective registration of morbidity, post-mortem interviews, and examination of available hospital records, a presumptive cause of death was established in 86% of the deaths. Persistent and acute diarrhoea were the most frequent causes of death, accounting for 43 and 31 deaths per 1000 children, respectively. Fever deaths (possibly malaria), neonatal deaths, acute respiratory infections, and measles were other frequent causes. The access to health services was relatively easy: 75% of the children who died had attended for treatment at a hospital or a health centre. It is important to find ways of preventing and managing persistent diarrhoea, the major cause of death, and to improve the control of acute diarrhoea by a targeted approach.     

Persistent reactive airway dysfunction syndrome after exposure to toluene diisocyanate

Two police officers developed asthma like illness after a single but prolonged exposure to toluene diisocyanate (TDI) by being in the immediate vicinity of a tank car that had overturned on a highway. One officer experienced upper and lower respiratory tract symptoms with chest tightness about 4.5 hours after initial exposure. Shortness of breath, cough, and wheezing were noted the following day. The other experienced symptoms immediately on exposure, developed shortness of breath 20 minutes later, and presented with wheezing four hours after that. Follow up examinations over seven years showed persistence of respiratory symptoms and continuation of airway hyperreactivity requiring treatment.     

Persistent reactive airway dysfunction syndrome after exposure to toluene diisocyanate.

Two police officers developed asthma like illness after a single but prolonged exposure to toluene diisocyanate (TDI) by being in the immediate vicinity of a tank car that had overturned on a highway. One officer experienced upper and lower respiratory tract symptoms with chest tightness about 4.5 hours after initial exposure. Shortness of breath, cough, and wheezing were noted the following day. The other experienced symptoms immediately on exposure, developed shortness of breath 20 minutes later, and presented with wheezing four hours after that. Follow up examinations over seven years showed persistence of respiratory symptoms and continuation of airway hyperreactivity requiring treatment.     

Escherichia coli diarrhoea

In recent years it has become clear that three types of Escherichia coli—enterotoxigenic, enteropathogenic, and enteroinvasive—play important roles in the etiology of acute diarrhoea. This report reviews the available knowledge on the epidemiology, clinical features, and pathophysiology of acute diarrhoea caused by these three types of E. coli, summarizes information on their laboratory diagnosis, and outlines priorities for further research. Particular attention is paid to important aspects of the relationship between enterotoxigenic E. coli diarrhoea in young animals and in man, and to recent advances in the development of E. coli vaccines for use in animals and their potential relevance to the development of an E. coli vaccine for use in man.     

Dealing with diarrhoea

Children with severe dehydration, persistent diarrhea with dehydration, or bloody diarrhea with no signs of improvement must be hospitalized. In-patient care for a child with severe dehydration includes rapid intravenous (IV) fluid therapy. Children who can still drink should be given oral rehydration salts (ORS) solution while the health worker sets up the IV drip. Children with difficulty drinking should be given ORS as soon as the IV fluid therapy restores their ability to drink (within 3-4 hours for babies, or 1-2 hours for older children), since ORS amends mineral deficiencies more effectively than the IV fluids. The IV drip should be re-administered if the child still exhibits dehydration after 3 hours for older children or 6 hours for babies. If improvement is noted, health workers should encourage the mother to administer ORS and to breast feed frequently. Hospital personnel should observe the child for at least 6 hours before discharge. This allows them to be sure that mothers can maintain the child's fluid balance. Children with diarrhea for more than 14 days face malnutrition or death. Any child with persistent diarrhea who exhibits moderate or severe malnutrition and signs of dehydration and is less than 4 months old needs to be admitted to a hospital. Management of persistent diarrhea involves fluid replacement, appropriate diet, and treatment of associated infections, if needed. ORS is usually effective for persistent diarrhea, although in a few cases poor absorption of glucose may necessitate initial rehydration with IV therapy. Breast feeding is encouraged for infants. Older infants and young children should eat 6 times a day as soon as they are able to eat. Recommended diets for these children are a low lactose diet (milk, yogurt, or curds; cooked rice; oil; sugar/glucose) and a low starch and no lactose diet (eggs, chicken, or fish; cooked rice; oil; sugar/glucose). Children with serious infections may require nasogastric feeding at first. Shigella bacteria tend to be responsible for dysentery. Children with this bloody diarrhea should be treated with an antibiotic. If their condition does not improve and they are malnourished, less than 1 year old, were initially dehydrated, or have recently had measles, they need to be hospitalized. Drugs to reduce frequency of stools should never be given in cases of bloody diarrhea. Older babies and children should be given an extra meal and supplementary vitamins and minerals each day for two weeks.     

Travellers' diarrhoea.

Travellers' diarrhoea affects 15-20 million people each year worldwide. Intestinal infection is the major cause and this can be partially prevented by avoidance of contaminated food and drink. Antimicrobial chemotherapeutic agents are also effective in preventing and treating the condition but widespread indiscriminant use is not recommended.     

Persistent hyperinsulinemic hypoglycemia in infancy: differentiated approach to a heterogeneous syndrome

Persistent hyperinsulinemic hypoglycaemia in infancy (PHHI) presents a diagnostic and therapeutic challenge for the treating physician: increased glucose requirements, detectable insulin levels at the point of hypoglycaemia, inappropriately low blood levels of free fatty acids and ketone bodies are characteristic of this condition. Despite recent developments in understanding its pathophysiology, treatment remains difficult and there are many long-term complications. Adequate treatment strategies are needed to prevent severe neurological damage. As there is a high possibility that hyperinsulinism may only be transient, aggressive pharmacological treatment is necessary for 4 to 6 weeks before moving on to surgical intervention. In the light of recent knowledge, routine subtotal pancreatectomy in children is no longer justifiable. An attempt should first be made to differentiate between focal and diffuse hypersecretion of insulin by using interventional radiology techniques, notably pancreatic venous sampling. This then enables targeted partial pancreatectomy.     

Evaluation of an algorithm for the treatment of persistent diarrhoea: a multicentre study. International Working Group on Persistent Diarrhoea.

Described are the findings of a multicentre cohort study to test an algorithm for the treatment of persistent diarrhoea relying on the use of locally available, inexpensive foods, vitamin and mineral supplementation, and the selective use of antibiotics to treat associated infections. The initial diet (A) contained cereals, vegetable oil, and animal milk or yoghurt. The diet (B) offered when the patient did not improve with the initial regimen was lactose free, and the energy from cereals was partially replaced by simple sugars. A total of 460 children with persistent diarrhoea, aged 4-36 months, were enrolled at study centres in Bangladesh, India, Mexico, Pakistan, Peru, and Viet Nam. The study population was young (11.5 +/- 5.7 months) and malnourished (mean weight-for-age Z-score, -3.03 +/- 0.86), and severe associated conditions were common (45% required rehydration or treatment of severe infections on admission). The overall success rate of the treatment algorithm was 80% (95% CI, 76-84%). The recovery rate among all children with only diet A was 65% (95% CI, 61-70%), and was 71% (95% CI, 62-81%) for those evaluated after receiving diet B. The children at the greatest risk for treatment failure were those who had acute associated illnesses (including cholera, septicaemia, and urinary tract infections), required intravenous antibiotics, and had the highest initial purging rates. Our results indicate that the short-term treatment of persistent diarrhoea can be accomplished safely and effectively, in the majority of patients, using an algorithm relying primarily on locally available foods and simple clinical guidelines. This study should help establish rational and effective treatment for persistent diarrhoea.     

痛泻要方加味治疗肠道易激综合征28例

目的:观察痛泻要方加味治疗肠道易激综合征疗效.方法:每日一剂,煎两次对匀,早晚各服一次.辅以精神安慰和 饮食指导.结果:总有效率达 89.29%,痊愈 60.71%,好转 28.57%,无效 10.71%.结论:痛泻要方加味是治疗肠 道易激综合征的一种切实可行的方法.