Differential Diagnosis for a Family of Four with Chronic Constipation and Malabsorption

The following differential diagnosis is organized into categories to help guide the thought process:

• Single Most Likely Diagnosis

  • Hookworm infection: Despite numerous negative stool cultures, hookworm infection remains a possibility, especially given the family's prolonged residence in Mexico, a region where hookworm is endemic. Chronic hookworm infection can lead to malabsorption and gastrointestinal symptoms, including constipation in some cases, due to the worm's attachment to the intestinal mucosa and feeding on blood and nutrients.

• Other Likely Diagnoses

  • Giardiasis: Another intestinal parasite that can cause malabsorption and gastrointestinal symptoms. It's common in areas with poor sanitation and can be difficult to diagnose with stool cultures alone.
  • Celiac Disease: An autoimmune disorder that causes the immune system to react to gluten, leading to malabsorption and various gastrointestinal symptoms. It can affect multiple family members if there's a genetic predisposition.
  • Tropical Sprue: A condition characterized by malabsorption and gastrointestinal symptoms, often seen in people living in tropical regions. The exact cause is unknown, but it's thought to be related to bacterial, viral, or parasitic infections.

• Do Not Miss Diagnoses

  • Intestinal Lymphoma: A type of cancer that can cause malabsorption and gastrointestinal symptoms. It's less common but critical to diagnose early due to its potential severity and the need for prompt treatment.
  • Whipple's Disease: A rare, systemic bacterial infection that can cause malabsorption, weight loss, and other systemic symptoms. It's crucial to diagnose due to its severity and the availability of effective antibiotic treatment.
  • Crohn's Disease or Ulcerative Colitis: Inflammatory bowel diseases that can cause chronic gastrointestinal symptoms, including constipation and malabsorption, especially if the disease is primarily localized to the colon.

• Rare Diagnoses

  • Abetalipoproteinemia: A rare inherited disorder that affects the absorption of fat and fat-soluble vitamins, leading to malabsorption and specific gastrointestinal symptoms.
  • Immunodeficiency Disorders: Certain immunodeficiencies can predispose individuals to opportunistic infections and malabsorption syndromes, presenting with chronic gastrointestinal symptoms.
  • Eosinophilic Gastroenteritis: A rare condition characterized by eosinophilic infiltration of the gastrointestinal tract, which can cause malabsorption, gastrointestinal symptoms, and sometimes constipation.