Schistosomiasis(bilharzia)

1. Schistosomiasis(bilharzia) By Dr. Karl

2. Sometimes referred to as bilharzias, bilharziasis, or snail fever, • is a parasitic disease caused by trematode(flukes) flatworms of the genus Schistosoma. • Belong to Phylum Platyhelminthes

3. History • schistosomiasiswas discovered by Theodore Bilharz, a German surgeon working in Cairo, who first identified the etiological agent Schistosomahematobium in 1851 • The first doctor who described the entire disease cycle was Pirajá da Silva in 1908. • It was a common cause of death for Ancient Egyptians in the Greco-Roman Period.

5. classification • Schistosomamansoni • Schistosomahematobium • Schistosomajaponicum • S. intercalatum • S. mekongi • ***Trichobilharziaocellata (cause swimmers itch) Four species routinely infect the human host, and several others rarely do so.

7. Schistosoma eggs (haematobium with terminal stings - mansoni with lateral stings)

9. Epidemiology • It is endemic to at least 76 tropical and sub-tropical countries. • more than 200 million people are infected worldwide. In terms of impact this disease is second only to malaria as the most devastating parasitic disease. Schistosomiasis is considered one of the Neglected Tropical Diseases (NTDs)

10. The disease is found in tropical countries in Africa, the Caribbean, eastern South America, Southeast Asia and in the Middle East. • Schistosomamansoniis found in parts of South America and the Caribbean, Africa, and the Middle East; • S. haematobiumin Africa and the Middle East; and S. japonicumin the Far East. • S. mekongiand S. intercalatumare found locally in Southeast Asia and central West Africa, respectively

13. Transmission • Risk Factor- Wading and swimming in fresh water in tropical regions • You get a schistosoma infection through contact with contaminated water. The parasite in its infective stages is called a cercaria. It swims freely in open bodies of water.

14. cercaria

15. Skin vesicles on the forearm, created by the penetration of Schistosoma

17. pathophysiology

18. Schistosomiasis is due to immunologic reactions to Schistosoma eggs trapped in tissues. Antigens released from the egg stimulate a granulomatous reaction involving T cells, macrophages, and eosinophils that results in clinical disease • Initially, the inflammatory reaction is readily reversible. In the latter stages of the disease, the pathology is associated with collagen deposition and fibrosis, resulting in organ damage that may be only partially reversible.

19. Photomicrography of bladder in S. hematobium infection, showing clusters of the parasite eggs with intense eosinophilia

25. Host

26. All snail species susceptible to infection with Schistosomamansoni and S. haematobium belong to the family Planorbidae in the subclass Pulmonata. • Schistosomamansoni infects snails in the genus Biomphalaria, and these can also become infected with S. mansoni-S. intercalatum hybrids, S. rodhaini and S. eduardiense. • Schistosomahaematobium infects pulmonate snails of the genus Bulinus. • Oncomelania for S japonicum • Tricula (Neotriculaaperta) for S mekongi

27. Clinical Presentation • Symptoms and signs depend on the number and location of eggs trapped in the tissues.

28. Eggs can end up in the skin, brain, muscle, adrenal glands, and eyes. As the eggs penetrate the urinary system, they can find their way to the female genital region and form granulomas in the uterus, fallopian tube, and ovaries. • Central nervous system (CNS) involvement occurs because of embolization of eggs from the portal mesenteric system to the brain and spinal cord via the paravertebral venous plexus.

29. location Intestinal Urinary S. hematobium • S. mansoni • S. japonicum • S. intercalatum • S. mekongi

30. S. japonicum eggs in hepatic portal tract

31. Acute schistosomiasis • Katayama syndrome- is a systemic, serum sickness-like illness that develops after several weeks in some, but not most, individuals with new schistosomal infections. • is associated with marked peripheral eosinophilia and circulating immune complexes • most common with S japonicum and S mansoniinfections • is most likely to occur in heavily infected individuals after primary infection

32. present usually 4-8 weeks after(exposure to S japonicum or S mansoni) contact with infested water • Fever, lethargy, malaise, and myalgia are the most common symptoms • Less common symptoms • cough, • headache, anorexia • rash (urticarial or papular) • Right upper quadrant pain and bloody diarrhea may also occur • patients may present with focal neurological deficits.

34. Chronic Intestinal Schistosomiasis • disease onset is insidious- Patients with symptomatic chronic schistosomiasis may present months to years after primary exposure • portal hypertension with splenomegaly oesophagialvarices, hypersplenism, ascitis, dyspepsia, flatulence, and pain are present in the left hypochondrium • pulmonary hypertension • CNS lesions: spine - transverse myelitis cerebral – seizures (S. japonicum) -Dizziness, nausea, and increased intracranial pressure, Visual scintillation from occipital mass

35. intestinal polyposis: intestinal granulomatosis: contractures of colon, intusseception, melena, Generalized lymphadenopathy • Female genital schistosomiasis- Postcoital bleeding, Genital ulceration, Irregular menstruation, Pelvic pain • Cardiopulmonary schistosomiasis - larval pneumonitis with a cough, mild wheezing, and a low-grade fever, while in schistosomalcorpulmonale, easy fatigability, palpitations, dyspnea on exertion, and hemoptysis

37. Splenomegaly due to bilharziosis: a drawing of the contour before ablation and the spleen after excision

40. Tortuous Varicosities in Chronic Schistosomiasis

41. Cercarial dermatitis of humans ("swimmer's itch", "Badedermatitis", "Weiherhippel") Trichobilharzia ocellata

42. Urinary schistosomiasis Schistosoma haematobium

43. Schistosoma near urethra

45. Presentation • hematuria (terminal) • urinary frequency • pyuria • pyelonephritis • obstructive uropathy • cancer of bladder (squamous cell) • distant metastases (spinal column) • (pulmonary hypertension)

49. diagnostics

50. symptoms mimic any acute viral, bacterial, or malarial illness. • Obtaining a careful travel history, including drinking water sources and recreational activities, is important. Symptoms are likely secondary to immune complex formation following egg deposition in tissues; the illness resembles serum sickness.