Schistosomiasis - Stepwards

Page Contents

1 WHAT IS IT?
2 WHY IS IT A PROBLEM?
3 WHAT MAKES US SUSPECT IT?
4 HOW DO WE CONFIRM A DIAGNOSIS?
5 HOW DO WE RULE OTHER DIAGNOSES OUT?
6 HOW DO WE TREAT IT?
7 HOW WELL DO THE PATIENTS DO?
8 WAS THERE A WAY TO PREVENT IT?
9 WHAT ELSE ARE WE WORRIED ABOUT?
10 OTHER HY FACTS?
11 AKNOWLEDGMENTS
12 FURTHER READING

WHAT IS IT?

Schistosomiasis is a tropical parasitic disease that is caused by blood-dwelling trematodes (flukes) of the Schistosoma genus.

The life cycle of this parasite is outlined in the image above (source) — The life cycle of the *Schistosoma* parasite is outlined in the image above (source)

WHY IS IT A PROBLEM?

Once a patient is infected with this parasite, it will spread to the liver and then can spread to other organs. The organism can damage these organ structures (due to chronic inflammation caused by trapping of eggs in these tissues).

Spread of the schisto parasite within the human host (source)

WHAT MAKES US SUSPECT IT?

Risk factors: recent swimming in snail infested waters (source of transmission)

Fever (Katayama fever) can be observed during acute infection.

Urinary symptoms including dysuria and hematuria can be seen in this condition.

Abdominal pain can be present in patients and MIGHT mimic signs of appendicitis in some cases. With this in mind, this disease typically manifests as right upper quadrant pain.

Diarrhea with or without blood may be present.

HOW DO WE CONFIRM A DIAGNOSIS?

Eosinophilia is present in many patients with acute disease.

CT scan can reveal signs of cirrhosis/liver damage in some chronic cases.

Patient with liver cirrhosis secondary to schistomiasis (source) — Patient with liver cirrhosis secondary to schistosomiasis (source)

Laparoscopy may reveal incidental liver/abdominal findings that warrant investigation of this disease. Ultimately biopsy of the liver can be useful in helping aid in the diagnosis.

Deposits of schisto eggs at the ovary and fallopian tube (seen during laparoscopy, source) — Deposits of *Schistosoma* eggs at the ovary and fallopian tube (seen during laparoscopy, source)

Microscopic analysis of blood or stool can detect the presence of schistosome eggs. This is the gold standard for diagnosis.

Visual appearance of (source) — Visual appearance of *Schistosoma haematobium* egg (source)

Serological testing can reveal the presence of Schistosoma antibodies (IgM and IgG) can reveal an infection with Schistosoma. This is best reserved within 2 months of the infection window (where eggs may not be present in urine/stool). PCR testing may also be an option depending on the test’s availability.

HOW DO WE RULE OTHER DIAGNOSES OUT?

While ultimately parasite specific testing will be the way to diagnose this condition, early on a CBC showing eosinophilia suggests that symptoms of this disease cannot necessarily be attributed to common diagnoses such as appendicitis alone.

HOW DO WE TREAT IT?

Praziquantel: is an anthelmintic used for the treatment of tapeworms and flukes.

HOW WELL DO THE PATIENTS DO?

The prognosis of the patient depends on when the condition is diagnosed and the extent of organ damage. This is a serious condition that can lead to very serious complications if left untreated (explained more below).

WAS THERE A WAY TO PREVENT IT?

Avoiding infection: refraining from swimming in snail infested waters is a clear way to prevent this disease form occurring.

WHAT ELSE ARE WE WORRIED ABOUT?

Untreated infection can leads to fibrosis of the liver and spleen, hepatosplenomegaly, and portal hypertension.

Pulmonary hypertension/pulmonary arterial hypertension can be caused by schistosomiasis

Bladder squamous cell carcinoma can be a complication of this disease.

OTHER HY FACTS?

Dystrophic calcifications can be seen in this condition.

This condition is sometimes a granulomatous disease

AKNOWLEDGMENTS

This page would not be possible without the expert teaching of (soon to be Dr.) Melanie Baskind.