What is the best course of treatment for a 4-year-old girl with abdominal distension and fever?

Immediate Evaluation and Management of a 4-Year-Old Girl with Abdominal Distension and Fever

This child requires urgent contrast-enhanced CT of the abdomen and pelvis to rule out life-threatening intra-abdominal pathology, including peritonitis, abscess, bowel perforation, or other surgical emergencies that commonly present with these symptoms in this age group. 1

Initial Assessment Priorities

The combination of abdominal distension and fever in a 4-year-old represents a potentially serious condition requiring immediate systematic evaluation:

• Assess for signs of peritoneal irritation including guarding, rebound tenderness, and rigidity, which suggest peritonitis or perforation requiring emergent surgical consultation 1
• Evaluate for signs of bowel obstruction including absent bowel sounds, colicky pain, and vomiting, as intestinal pseudo-obstruction can present with fever and distension 2, 3
• Check for abdominal wall bruising or tenderness as these may indicate occult trauma, with up to 10% of abused children having intra-abdominal injury 1
• Document fever pattern and measure rectal temperature to confirm fever ≥38°C (100.4°F), as this is the most reliable method in young children 1

Critical Diagnostic Workup

Contrast-enhanced CT of the abdomen and pelvis is the gold standard imaging modality for acute evaluation of suspected intra-abdominal pathology in children with fever and distension 1:

• CT can identify peritonitis, intra-abdominal abscess, bowel perforation, appendicitis, intussusception, and solid organ injuries 1
• Noncontrast CT is inadequately sensitive and should not be used 1
• Ultrasonography should be performed first to confirm ascites, differentiate fluid from organomegaly, and identify associated abnormalities, but has limited sensitivity for detecting solid organ injuries and hemoperitoneum compared to CT 1

Laboratory evaluation must include:

• Complete blood count with differential to assess for leukocytosis suggesting bacterial infection 1
• Liver transaminases and pancreatic enzymes, as elevated levels may indicate occult abdominal trauma even without obvious external signs 1
• Blood cultures if the child appears ill or has high fever ≥39°C, as bacteremia can complicate intra-abdominal infections 1
• If ascites is present, diagnostic paracentesis should be performed when the cause is unclear or spontaneous bacterial peritonitis is suspected 1

Differential Diagnosis Framework

The most critical conditions to exclude in this presentation include:

Infectious/Inflammatory Causes:

• Tuberculous peritonitis presents with slowly progressive abdominal distension, fever (44.4% of cases), and pain, with ascites and septations on ultrasound 4
• Spontaneous bacterial peritonitis in children with underlying liver disease or ascites from other causes 1
• Appendicitis with perforation can present with diffuse distension and fever 1

Mechanical/Obstructive Causes:

• Hirschsprung-associated enterocolitis (HAEC) classically presents with abdominal distension, fever, and diarrhea, occurring in 20-60% of Hirschsprung patients 3
• Intestinal pseudo-obstruction can present with persistent fever and progressive distension, as seen in Kawasaki disease complications 2

Traumatic Causes:

• Occult abdominal trauma from child abuse should be considered, as victims tend to be younger with delayed presentation, and abdominal distension with fever may indicate bowel perforation or abscess formation 1
• Bowel injuries and pancreatic injuries are disproportionately more common in abuse compared to accidental trauma 1

Immediate Management Algorithm

Step 1: Stabilization and Initial Assessment

• Establish IV access and begin fluid resuscitation if signs of dehydration or sepsis are present 1
• Keep the child NPO (nothing by mouth) until surgical pathology is excluded 1
• Administer antipyretics for fever control and analgesia for comfort 1

Step 2: Imaging and Laboratory Studies

• Obtain abdominal ultrasound first to assess for ascites, organomegaly, and free fluid 1
• Proceed immediately to contrast-enhanced CT abdomen/pelvis if ultrasound is abnormal or clinical suspicion remains high 1
• Complete laboratory workup as outlined above 1

Step 3: Specialist Consultation

• Urgent pediatric surgery consultation if imaging reveals peritonitis, perforation, abscess, or bowel obstruction 1, 2
• Infectious disease consultation if tuberculous peritonitis or other complex infection is suspected 4
• Gastroenterology consultation if ascites is present and etiology unclear 1

Step 4: Empiric Antibiotic Therapy

• If the child appears ill, toxic, or has signs of peritonitis, initiate broad-spectrum IV antibiotics covering gram-positive, gram-negative, and anaerobic organisms before definitive diagnosis 1, 5
• Metronidazole is indicated for intra-abdominal infections including peritonitis and intra-abdominal abscess caused by anaerobic bacteria 5

Critical Pitfalls to Avoid

• Do not rely on ultrasound alone for excluding serious intra-abdominal pathology, as it is less sensitive than CT for detecting solid organ injuries and bowel perforation 1
• Do not delay imaging for laboratory results if the child appears ill or has peritoneal signs 1
• Do not miss occult child abuse by failing to assess for inconsistent history, delayed presentation, or associated injuries such as bruising or fractures on skeletal survey 1
• Do not use antimotility agents in any child with fever and abdominal distension, as toxic megacolon may result if inflammatory diarrhea is present 1
• Do not perform routine chest physiotherapy as it is not beneficial and should not be done 1

Hospital Admission Criteria

This child requires hospital admission given the combination of fever and abdominal distension, which suggests potentially serious pathology requiring close monitoring, IV antibiotics, and possible surgical intervention 1.