What is the appropriate workup and treatment for an 18-month-old child who ingested cat feces and now presents with vomiting, fever, and diarrhea?

Workup and Management for 18-Month-Old with Ingestion of Cat Feces and Gastroenteritis Symptoms

For an 18-month-old who ingested cat droppings and now presents with vomiting, fever, and diarrhea, the immediate workup should include assessment for dehydration, stool studies for parasites and bacteria, and appropriate rehydration therapy based on severity of dehydration. 1

Initial Assessment

• Evaluate the degree of dehydration based on clinical signs (skin turgor, mucous membranes, mental status, capillary refill time) 2
• Categorize dehydration as:
  • Mild (3-5% fluid deficit): slightly dry mucous membranes, normal to slightly decreased skin turgor
  • Moderate (6-9% fluid deficit): dry mucous membranes, decreased skin turgor, sunken eyes
  • Severe (≥10% fluid deficit): very dry mucous membranes, significantly decreased skin turgor, sunken eyes, altered mental status 2

Laboratory Workup

• Stool studies are indicated due to the ingestion of cat feces, which raises concern for parasitic infection (especially Toxoplasma) 2
• Stool culture is particularly important given the bloody diarrhea, which may indicate bacterial or parasitic infection requiring antimicrobial treatment 2
• Serum electrolytes should be measured if there are clinical signs suggesting abnormal sodium or potassium concentrations 2

Rehydration Therapy

• For mild dehydration (3-5% fluid deficit):

  • Administer 50 mL/kg of oral rehydration solution (ORS) over 2-4 hours 2, 1
  • Use small volumes (5-10 mL) administered every 1-2 minutes via spoon, syringe, or cup, gradually increasing the amount 2

• For moderate dehydration (6-9% fluid deficit):

  • Administer 100 mL/kg of ORS over 2-4 hours 2, 1
  • Use the same small-volume approach as for mild dehydration 2

• For severe dehydration (≥10% fluid deficit):

  • Immediate IV rehydration with boluses (20 mL/kg) of Ringer's lactate solution or normal saline until pulse, perfusion, and mental status normalize 2
  • Once stabilized, transition to oral rehydration 2

Ongoing Fluid Replacement

• Replace ongoing stool losses with 10 mL/kg of ORS for each watery stool 2, 1
• Replace vomiting losses with 2 mL/kg of ORS for each episode of emesis 2, 1
• For intractable vomiting, consider continuous, slow nasogastric infusion of ORS 2

Nutritional Management

• Continue breastfeeding if applicable 1
• Resume normal diet immediately after rehydration; do not withhold food 1
• For bottle-fed infants, consider lactose-free or lactose-reduced formulas if there are signs of lactose intolerance 2

Medication Considerations

• Avoid antimotility drugs (loperamide) as they are contraindicated in children under 18 years with acute diarrhea 1
• Consider antiemetics (ondansetron) for children over 4 years with severe vomiting to facilitate oral rehydration 1
• Antimicrobial therapy may be necessary if stool studies confirm parasitic or bacterial infection 2

Warning Signs Requiring Immediate Medical Attention

• Inability to tolerate oral fluids 1
• Worsening signs of dehydration 1
• Bloody diarrhea 2
• Significant increase in fever 1
• Altered mental status 2

Common Pitfalls to Avoid

• Allowing the child to drink large volumes of ORS ad libitum, which can worsen vomiting 2
• Withholding food during diarrheal illness, which can worsen nutritional status 1
• Failing to recognize glucose malabsorption, indicated by increased stool output with ORS administration 2
• Neglecting to assess for dehydration regularly during treatment 2