DIARRHOEAL DISEASES / MedUrgent
DIARRHOEAL DISEASES
watery diarrhea is defined as abnormally loose or fluid stools more than 3 times per day.
mothers opinion regarding diarrhea onset is more important than the number of motions.
Diarrheal disease is the 3rd highest cause of death due to infection in the world with 1-2 million deaths each year globally and 80% of deaths occur among those less than 2 years of age.it is divided according to the presence or absence of blood in the stools since the underlying causes are generally different.
Persistent diarrhea (lasting for more than 14 days) needs special consideration.
Patients with acute diarrheal disease should have the following laboratory test done: Stools microscopy and culture, CBC, U&E, Blood Glucose BF for Malaria and RotaVirus Antigen.
ACUTE DIARRHEA WITH BLOOD IN THE STOOLS
The Infective causes of acute diarrhea with blood include:
. Bacillary Dysentery (shigellosis)
• Enterohemorrhagic E.coli
• Campylobacter enterocolitis
• Salmonella enterocolitis
• Clostridium difficile colitis
• Yersinia enterocolitis
•Amoebic dysentery
• Massive trichuris infection
• Schistosomiasis
Enterohemorrhagic E.coli (EHEC)
EHEC produces a cytotoxin leading to inflammatory colitis, hemorrhagic colitis and hemolytic uremic syndrome. The commonest serotype is 0157.
Contaminated food is the most common source of infection.
Clinical features include: watery diarrhea that changes to diarrhea with blood within 2-3 days.vomitting and abdominal pain are common.
Management includes supportive therapy and rehydration. Antibiotics and anti-motility drugs should be avoided.
Campylobacter enterocolitis
c ieiuni causes epidemics in pediatric wards and nurseries. A common carrier is frozen food, meat and chicken. Clinical features include fever, diarrhea with blood and abdominal pain. Complications include bacteraemia, meningitis, abscesses, cholecystitis reactive arthritis and Guillain-Barre syndrome. Management includes supportive therapy and antibiotics for severe cases (erythromycin or trimethoprim sulfa methoxzole or ciprofloxacin may be used).
Yersinia enterocolitica
Similarly, the common carriers are frozen food, meat and chicken. Y. enterocolitica causes diarrhea with blood, abdominal pain, nausea, vomiting, headaches and low grade fever. Complications include peritonitis, osteomyelitis, and muscle abscesses. Liver, kidneys and spleen may be affected. Treatment of severe cases includes gentamicin or ciprofloxacin or doxycycline in adults. Other organisms that can cause bloody diarrhea are described in relevant sections.
ACUTE DIARRHOEA WITHOUT BLOOD
Rota virus:
This is a wheel-shaped RNA virus that affects more than 60% of children under five years. Rota virus is one of the commonest causes of watery diarrhea worldwide. It tends to be more severe in children months but it can affect all age groups. It selectively destroys" small intestinal villi in a patchy manner leading to imbalance of fluid absorption and thus increased intraluminal fluid overload resulting in acute watery diarrhea.
re in children 3-24
disease. It presents with mild fever, vomiting and watery diarrhea, Fever and vomiting abate for 5-7 days. Isotonic dehydration which occurs rapidly associated with acidosis is commonly found. Abdominal pain and exaggerated bowel second are occasionally experienced. Recurrent infections can develop but with decreasing severity.
The diagnosis can be determined by enzyme immunoassay, PCR and stools culture. The virus can be seen under the electron microscope.
Management includes supportive therapy; Zinc, probiotics, diet and dehydration according to the degree of dehydration. Antiemetic, antidiarrheal drugs and antibiotics have no role in the treatment and can be associated with serious side effects. Rota vaccine is recently introduced in Sudan
Others viruses that can cause watery diarrhea include astrovirus, calicivirus such as the Norfolk Agent, adenovirus, coronavirus, poliovirus, measles and influenza virus.
Enterotoxigenic E.coli (ETEC)
ETEC is transmitted by feco-oral route and contaminated food is the main source. ETEC strains adhere to mucosal cells of the small intestine and produce two types of toxins, Heat labile enterotoxin (LT) and heat stable enterotoxin (ST). These toxins do not injure or kill cells; they disturb cyclic nucleotides that regulate fluid and electrolyte absorption. They activate the cyclic AMP within the enterocyte and in addition to calcium molecules that lead to out flux of water and electrolytes into the intestinal lumen (LT secretory diarrhea is similar to cholera) leading to losses of large amounts of watery diarrhea and abdominal pain. Dehydration ensues rapidly in children. ST Enterotoxins produce similar intracellular reactions leading to severe secretory diarrhea.
Enteropathogenic E.coli (EPEC)
This type adheres and destroys the intestinal mucosal microvilli leading to prolonged mucoid-watery diarrhea, vomiting and fever.Attachment results in increased intracellular calcium concentration which leads to secretory diarrhea.
Production of an endotoxin has also been mentioned as a possible cause.it has been associated with outbreaks of infantile gastroenteritis.
Enteroinvasive E.coli (EIEC)
Entero Aggressive E.coli (EAEC) & Diffuse-adhérent E.coli (DAEC)
These organisms are referred to as autoagglutination and enteroadherent E Coli. They produce heat stable and heat labile toxins and cause diarrhea in infants, school children and are a recognized cause of "traveler's diarrhea". Watery diarrhea is often persistent.
Management of E.coli infections is often supportive; however, antibiotics (trimethoprim sulfamethoxazole or ciprofloxacin) are used in severe cases.
CHOLERA:
This is acute fulminant watery diarrhea which, if untreated, may be fatal due to severe dehydration. The causative organism is Vibrio cholera which is gram-negative, aerobic, comma-shaped bacteria. Its main reservoir is human carriers and is transmitted through water and infected food. It can be killed by heating and disinfectants. Incubation period ranges from a few hours to 5 days. Although the classical Vibrio Cholera is still endemic in the Far East in countries like India, Bangladesh and adjacent countries, the El Tor biotype has spread to many countries of the world. The rate of asymptomatic carriers during epidemics is high especially for the serotype El Tor, which is now endemic in many countries in Asia, Africa including Sudan, South America and some parts in Europe. Although children can be infected. Yet, those under 1 year are usually exempt.
Clinical features include severe rice water diarrhea (up to 30 liters per day in adults), leading to severe dehydration, electrolyte imbalance , acidosis, prostration and death. Vomiting starts shortly after diarrhea. Children may have mild fever.Other features include impaired consciousness, hypovolemic shock, renal failure, ileus and arrhythmias
Management includes rehydration both by IV & oral. In case of rapid and severe losses more than one IV line is fixed and at fast rates.
losses and some may reduce the bacterial load. Tetracycline used in adult patients reduces the stool output significantly and furazolidone has a similar effect in children.
Food and water hygiene and the use of disinfectants are important measures to control epidemics.
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