How to approach a patient with fever, ascites, hepatosplenomegaly, and rash?

Approach to a Patient with Fever, Ascites, Hepatosplenomegaly, and Rash

The most effective approach to a patient with fever, ascites, hepatosplenomegaly, and rash is to prioritize evaluation for tropical infections, particularly schistosomiasis (Katayama syndrome) and dengue, as these conditions commonly present with this constellation of symptoms and require prompt diagnosis and treatment.

Initial Assessment

Travel History

• Obtain a detailed geographical history including countries visited, time of onset and duration of symptoms 1
• Most tropical infections become symptomatic within 21 days of exposure 1
• Document locations visited, dates of travel, dates of symptom onset and risk activities on all laboratory request forms 1

Clinical Evaluation

• Assess for specific features that may suggest the underlying diagnosis:
  • Urticarial rash with fever after freshwater exposure suggests Katayama syndrome (acute schistosomiasis) 1, 2
  • Macular rash with petechiae and hemorrhagic manifestations suggests dengue 3, 4
  • Lymphadenopathy with fever and rash may indicate lymphoproliferative disorders 5, 6

Diagnostic Workup

Essential Initial Investigations

• Complete blood count with differential to check for:
  • Eosinophilia (>0.45 × 10^9/L): suggests parasitic infection, particularly schistosomiasis 1
  • Thrombocytopenia: common in dengue and other viral infections 1, 3
  • Lymphopenia: common in viral infections and typhoid 1
• Malaria film and rapid diagnostic test (RDT) for all patients who have visited a tropical country within 1 year 1
• Blood cultures (two sets) prior to antibiotic therapy 1
• Liver function tests to assess pattern and severity of liver involvement 1
• Renal function tests 1
• Urinalysis for proteinuria and hematuria 1
• Serum save for serological testing 1
• EDTA sample for PCR if arboviral infection is suspected 1

Imaging Studies

• Abdominal ultrasound to assess:
  • Extent of hepatosplenomegaly 3
  • Presence and quantity of ascites 3
  • Gallbladder wall thickening (common in dengue) 3
• Chest X-ray to evaluate for pleural effusions 1

Differential Diagnosis

Tropical Infections

• Schistosomiasis (Katayama syndrome)

  • Presents 2-9 weeks after freshwater exposure in endemic areas 1, 2
  • Characterized by fever, urticarial rash, eosinophilia, and hepatosplenomegaly 1, 2
  • Diagnosis is often clinical as serology may be negative early in disease 2

• Dengue

  • Characterized by fever, rash, myalgia, arthralgia, and hepatosplenomegaly 1, 3
  • Can progress to dengue hemorrhagic fever with pleural effusion and ascites 3, 4
  • Diagnosis by PCR or IgM capture ELISA 1

• Other Parasitic Infections

  • Visceral larva migrans (Toxocara): fever, eosinophilia, hepatosplenomegaly 1
  • Loeffler's syndrome: fever, urticaria, wheeze from nematode larval migration 1

Non-Tropical Conditions

• Lymphoproliferative Disorders

  • Angioimmunoblastic T-cell lymphoma can present with fever, rash, hepatosplenomegaly 5
  • TAFRO syndrome (variant of Castleman's disease): fever, ascites, hepatosplenomegaly 6

• Autoimmune/Inflammatory Conditions

  • Primary sclerosing cholangitis: can present with hepatosplenomegaly, pruritus, and jaundice 1
  • Drug-induced liver injury: may present with rash, fever, eosinophilia 1

Management Approach

For Suspected Schistosomiasis (Katayama Syndrome)

• Empiric treatment is warranted when there is a combination of freshwater exposure 4-8 weeks previously, fever, urticarial rash, and eosinophilia 1, 2
• Praziquantel 40 mg/kg as a single dose, repeated at 6-8 weeks (as eggs and immature schistosomules are relatively resistant) 1, 2
• Consider short course of steroids (oral prednisolone 20 mg/day for 5 days) to alleviate acute symptoms 1

For Suspected Dengue

• Supportive care with fluid management and monitoring for complications 3, 4
• Monitor platelet counts, hematocrit, and liver enzymes 3
• Watch for warning signs of severe dengue: rapid decline in platelet count, hepatomegaly >2 cm, mucosal bleeding, and fluid accumulation 3

For Other Conditions

• Loeffler's syndrome: empirical treatment with albendazole 400 mg twice daily for 3 days when investigations are negative 1
• Lymphoproliferative disorders: corticosteroids and immunosuppressants may be required 5, 6

Special Considerations and Pitfalls

• Do not delay empiric treatment for schistosomiasis when clinical suspicion is high, even if initial serology is negative 1, 2
• Serology for schistosomiasis may take up to 6 months to become positive 1
• Patients with dengue may rapidly progress from mild symptoms to severe disease with shock 3, 4
• Consider multiple infections in returning travelers (up to 28% of patients in some studies) 1
• Document travel history clearly on all laboratory request forms to ensure appropriate testing 1