What is the recommended course of action for a patient with foul-smelling umbilical discharge and abdominal pain, but no fever?

Foul-Smelling Umbilical Discharge with Abdominal Pain: Urgent Evaluation and Management

This patient requires immediate hospital admission and CT abdomen/pelvis with IV contrast to evaluate for serious intra-abdominal complications, even without fever. 1

Critical Red Flags in This Presentation

The combination of foul-smelling umbilical discharge and abdominal pain represents a potentially life-threatening condition requiring urgent evaluation, regardless of fever absence:

• The umbilicus provides direct vascular access to intra-abdominal structures, making even painless discharge concerning for serious complications including intra-abdominal abscess, portal/umbilical vein thrombophlebitis, peritonitis, or bowel ischemia 1
• Abdominal pain with umbilical discharge indicates progression beyond simple superficial infection and suggests deeper pathology requiring immediate imaging 1
• Foul-smelling discharge strongly suggests anaerobic bacterial infection or necrotic tissue, which can rapidly progress to sepsis even without fever initially 1

Immediate Diagnostic Workup

Imaging (First Priority)

Obtain CT abdomen and pelvis with IV contrast immediately - this is the definitive imaging modality for this presentation:

• CT changes the diagnosis in 49% of patients with nonlocalized abdominal pain and alters management in 42% of cases 2, 3
• CT with IV contrast is specifically recommended for evaluating suspected intra-abdominal infection and can detect abscesses, phlegmons, urachal remnants, perforated viscus, and other serious pathology 2
• In patients with fever and abdominal pain, CT revealed the source of sepsis in multiple studies and changed admission status in 24% of cases 2
• The absence of fever does NOT eliminate the need for comprehensive imaging, as serious infections can present without fever, particularly in elderly or immunocompromised patients 3

Laboratory Studies

Obtain these concurrently with imaging arrangements:

• Culture the umbilical discharge to identify bacterial pathogens (Staphylococcus aureus, Streptococci, Gram-negative bacilli including E. coli, Klebsiella, Pseudomonas) and guide antibiotic therapy 1
• Complete blood count - leukocytosis >14,000 suggests infection or ischemia, though normal values do not exclude serious infection 3
• Metabolic panel with lactate - elevated lactate, low bicarbonate indicate potential intestinal ischemia 3
• Blood cultures if patient appears toxic or immunocompromised, as bacteremia may influence duration of therapy 2

Physical Examination Priorities

Assess immediately for signs requiring emergency surgical intervention:

• Peritoneal signs (guarding, rebound tenderness, rigidity) suggest perforation or ischemia and mandate urgent surgical consultation 3
• Periumbilical erythema or tenderness indicates progression to omphalitis with abdominal wall cellulitis 1
• Hemodynamic instability (tachycardia, hypotension) indicates potential sepsis or bowel ischemia requiring emergency intervention 3

Differential Diagnosis for Adult Umbilical Discharge with Abdominal Pain

The foul-smelling nature and abdominal pain narrow the differential to serious pathology:

• Infected urachal remnant (sinus, cyst, or patent urachus) - most common structural cause in adults, requires surgical excision after infection control 4, 5, 6
• Omphalitis with intra-abdominal extension - can lead to portal vein thrombophlebitis, peritonitis, or abdominal wall abscess 1, 4
• Umbilical pilonidal sinus - presents with bloody/purulent discharge and pain, requires surgical excision 7
• Perforated viscus with fistula formation - rare but reported (e.g., gallbladder perforation presenting as umbilical fistula) 8

Initial Management Algorithm

If Hemodynamically Stable:

1. Admit to hospital for observation and IV antibiotics 1
2. Start broad-spectrum IV antibiotics immediately while awaiting imaging and culture results 2
   • For non-critically ill adults: Amoxicillin/clavulanate 2g/0.2g IV q8h 2
   • For critically ill or immunocompromised: Piperacillin/tazobactam 6g/0.75g loading dose, then 4g/0.5g q6h 2
3. Obtain CT abdomen/pelvis with IV contrast urgently (within hours, not days) 2, 1
4. Surgical consultation for potential source control intervention 2

If Hemodynamically Unstable or Peritonitis Present:

1. Emergency surgical consultation immediately 2, 3
2. Aggressive IV fluid resuscitation 2, 3
3. Broad-spectrum antibiotics as soon as possible (do not delay for imaging) 2
4. Emergency laparotomy if diffuse peritonitis present 2

Source Control Considerations

Source control is essential for nearly all patients with intra-abdominal infection and should not be delayed beyond 24 hours in stable patients receiving appropriate antibiotics 2:

• Percutaneous drainage is preferable to surgical drainage where feasible for well-localized abscesses 2
• Surgical excision of urachal remnants is curative and prevents recurrence and malignant transformation 5, 6
• Simple topical antibiotics are inadequate when abdominal pain is present - this indicates deeper infection requiring systemic therapy and likely intervention 1

Critical Pitfalls to Avoid

• Do not assume absence of fever means absence of serious infection - elderly and immunocompromised patients frequently present with normal vital signs despite life-threatening infections 3
• Do not treat with oral antibiotics and outpatient follow-up - the combination of discharge and abdominal pain mandates admission and imaging 1
• Do not delay imaging to "see if antibiotics work" - CT changes diagnosis in half of cases and delays can lead to preventable complications 2
• Do not rely on ultrasound alone - while ultrasound may detect some abnormalities, CT with IV contrast provides comprehensive evaluation of intra-abdominal pathology 2

Antibiotic Duration

• Continue antibiotics for 2-4 days post-intervention if source control is adequate in immunocompetent, non-critically ill patients 2
• Extend to 7 days in immunocompromised or critically ill patients based on clinical response 2
• Patients with ongoing signs of infection beyond 7 days warrant repeat diagnostic investigation for inadequate source control 2