Today in report we discussed a case of granulomatous liver disease marked by evidence of portal hypertension in a patient with ESRD who presented w/ AMS responsive to lactulose. The patient eventually was found to have very positive schisto serologies, and given the path results, her portal HTN was deemed 2/2 to chronic schisto. Woah!
A bit about schistosomiasis:
Schistosomiasis is caused by infection with Schistosoma blood flukes that are endemic to parts of Africa, South America, East Asia, and the Middle East. These parasites live in freshwater snails and contaminate water sources. Infection can occur through skin contact!
It is estimated that ~200 million people worldwide are infected, with the highest concentrations in sub-Saharan Africa.
Pathogenesis and disease manifestations:
Most of those infected actually do not have symptomatic illness. Intensity of infection is usually worst during the 1st 2 decades of life presumably due to increased immune response during this time.
The clinical manifestations of schisto are broken down into acute and chronic.
Acute schistosomiasis syndrome (aka Katayama fever!): this is an acute hypersensitivity reaction to schisto antigens that occurs 3-8 wks after acute infection. This occurs mostly in people without prior exposure (travelers). Associated activities include fresh water exposures. Symptoms include fevers, urticarial, angioedema, chills, diarrhea, headache. Eos >1000 are usually seen within several days after onset of symptoms.
Swimmer’s itch: This is a localized dermatitis that occurs after repeated exposures. Usually on feet or lower legs
This most commonly occurs in patients with repeated or ongoing schisto exposures, but can sometimes occur in travelers. The clinical manifestations occur depending on where eggs are deposited.
Most common organs involved include: intestines (abd pain, diarrhea), liver/spleen (non fibrotic granulomas, pre-sinusoidal portal HTN!), lungs (pulm HTN w/ egg deposition in distal pulmonary arterioles, especially w/ portal vein collateralization w/ liver involvement), genitourinary system (macroscopic hematuria w/ S. haematobium, increased risk bladder Ca), glomerular system (nephrotic syndrome), CNS (transverse myelitis, seizures)
In a patient from an endemic area, serology is the most useful test, but may not represent active infection but instead previous infection and clearance. Antigen detection and PCR testing are in the works, but not yet clinically available.
Biopsy specimens typically show granulomas surrounding eggs (remember to keep schisto on your granuloma ddx!)
Praziquantel to treat the infection +/- steroids to deal with the acute inflammatory response in new infection or w/ neuro involvement.