Chronic Nonspecific Diarrhea
When diarrhea persists for longer than 3 weeks, it is said to be chronic condition. Chronic nonspecific diarrhea (CNSD) presents in toddlers between 18 months and 3 years of age, with frequent, large, watery stools in the absence of physical or laboratorysigns of malabsorption or infection and without effect on growth or development.
Children have 3 to 6 large, watery bowel movements daily.
Factors causing chronic nonspecific diarrhea
- Excess fluid intake
- Carbohydrate malabsorption from excessive juice ingestion
- Disordered intestinal motility
- Excessive fecal bile acids
- Low fat intake
Normally, CNSD occurs when fluid intake exceeds the absorptive capacity of the intestinal tract.Malabsorption of carbohydrates (sucrose, fructose, sorbitol) in fruit juices contributes to CNSD.
CNSD presents between 18 months and 3 years, with 3-6 large, loose, watery stools per day for more than 3 weeks.
Stooling is most frequent in the morning and does not occur during sleep. There is an absence of nausea, vomiting, abdominal pain, flatulence, blood, fever,anorexia, weight loss, or poor growth.
2. Clinical evaluation of chronic nonspecific diarrhea
The current number and type of stools should be determined. A diet history should determine the total calories, fat, milk and juice consumed daily, and it should assess prior trials of food elimination.
The timing of introduction of foods into the diet relative to the onset of diarrhea, and a 3-day diet history should be assessed. Usage of antibiotics, vitamins, iron, and medications should be sought.
A family history of irritable bowel syndrome, celiac disease, inflammatory bowel disease, infectious diarrhea, or food allergies should be sought.
Growth chart plotting of weight, height, and head circumference are essential. Children who have chronic nonspecific diarrhea should continue to grow normally, deviation from the growth chart or a downward trend suggests inadequate caloric intake or a disease other than CNSD.
Signs of malnutrition or malabsorption include lack of subcutaneous fat, eczematoid rash (from essential fatty acid deficiency), glossitis, easy bruising, or hyporeflexia.
A fresh stool specimen is tested for neutral fat, pH and reducing substances, occult blood, and Giardia antigen. Neutral fat suggest pancreatic insufficiency.
Fecal pH and reducing substances will reveal carbohydrate malabsorption if the pH is less than 5.5 or if reducing substances are greater than 1+.
Occult fecal blood is inconsistent with CNSD unless there is a perianal rash.
3. Differential diagnosis
The differential diagnosis of chronic diarrhea in the 6- to 36-month-old child includes disaccharidase deficiency, protein intolerance, enteric infection, and malabsorption.
- Lactase deficiency may cause diarrhea associated with milk ingestion.
- Congenital lactase deficiency is extremely rare and symptoms are present from birth if an infant is fed human milk or a lactose-containing formula.
- Genetically acquired lactase deficiency is common, but it usually is not symptomatic before 5 years of age.
Disaccharidase deficiency can be confirmed by eliminating the specific carbohydrate or by breath hydrogen analysis.
Milk-induced colitis occurs in infants younger than 1 year of age who typically appear healthy but lose blood in their stool after ingesting milk protein. Infants who have milk-induced enterocolitis are younger, less than 3 months of age. These infants may be severely ill with bloody diarrhea, hypoproteinemia, and growth failure. Children who have protein allergies tend to come from families that have allergic histories, and affected children may have eczema, allergic rhinitis, asthma.
Malabsorption presents with chronic diarrhea, weight loss, poor appetite, weakness and decreased activity, bloating and flatulence, abdominal pain, and chronic vomiting. Chronic diarrhea and failure to thrive warrants a sweat test. Celiac disease must be confirmed by intestinal biopsy.
4. Management of CNSD
Fluid intake should be reduced to less than 100 mL/kg/day. Water is substituted for juice to reduce the child's interest in drinking.Switching from the bottle to the cup also decreases fluid intake.
Fat intake is increased to 4 g/kg/day by adding whole milk to the diet. If lactose intolerance is present, low-lactose milk can be used or lactase drops can be added to milk. Butter, margarine, or vegetable oil are liberally added to foods for children less than 2 years of age.
Dietary fiber can be increased by consumption of fresh fruits and vegetables or by the addition of bran.