Differential Diagnosis for a 12-Month-Old Girl with Diarrhea
- Single Most Likely Diagnosis
- Toddler's diarrhea (or chronic nonspecific diarrhea): This condition is characterized by the onset of loose, bulky stools in a previously healthy toddler, often following an episode of acute gastroenteritis. The symptoms described, such as bulky and malodorous stools without blood or mucus, and the absence of systemic symptoms like fever or vomiting, are typical for this diagnosis. The improvement after an initial illness followed by worsening diarrhea upon resuming a regular diet, including whole milk, further supports this diagnosis.
- Other Likely Diagnoses
- Lactose intolerance: Given the worsening of diarrhea after the girl resumed her regular diet including whole milk, lactose intolerance is a plausible diagnosis. This condition occurs when the body is unable to digest lactose, a sugar found in milk, due to a deficiency of the enzyme lactase.
- Dietary indiscretion or food intolerance: Other food intolerances or dietary factors could be contributing to the girl's symptoms, especially if she has recently been introduced to new foods or has an excessive intake of certain food groups.
- Do Not Miss Diagnoses
- Inflammatory bowel disease (IBD): Although less common in this age group, conditions like Crohn's disease or ulcerative colitis can present with chronic diarrhea, abdominal distension, and malabsorption. It's crucial to consider IBD to avoid missing a potentially serious condition that requires specific management.
- Intestinal infection (e.g., giardiasis): Certain infections can cause prolonged diarrhea in children. Giardiasis, for example, can lead to malabsorption and chronic diarrhea, and it's essential to rule out such infections, especially if the child has been exposed to contaminated water or has traveled to areas where such pathogens are common.
- Celiac disease: An autoimmune reaction to gluten can cause chronic diarrhea, abdominal distension, and malabsorption in children. Early diagnosis is critical to prevent long-term complications.
- Rare Diagnoses
- Congenital disorders of glycosylation: These are a group of rare genetic disorders that can affect the body's ability to digest and process sugars, leading to symptoms including diarrhea.
- Sucrose-isomaltase deficiency: A rare genetic disorder that affects the ability to digest certain sugars, leading to chronic diarrhea and malabsorption.
- Other enzymatic deficiencies (e.g., pancreatic insufficiency): Conditions affecting the pancreas or other digestive enzymes can lead to malabsorption and chronic diarrhea, though these are less common in previously healthy toddlers.