Cervix - Cytology
Inflammation / parasites
Schistosomiasis

Author: John Philip, M.D. (see Authors page)

Revised: 15 May 2017, last major update March 2015

Copyright: (c) 2003-2017, PathologyOutlines.com, Inc.

PubMed Search: Schistosomiasis [title] cervix
Cite this page: Cytology - Schistosomiasis. PathologyOutlines.com website. http://pathologyoutlines.com/topic/cervixcytologyschistosomiasis.html. Accessed August 18th, 2017.
Definition / general
  • Infestation of the parasite Schistosoma in female genital tract
  • Also called Bilharziasis after German physician Theodor Bilharz, who described the first case of urinary schistosomiasis in 1851
  • See also Parasitology chapter
Epidemiology
  • More common in Africa and Middle East
  • Rare in United States and Europe
  • In endemic areas, prevalence of female genital schistosomiasis ranges from 30 - 75% (Acta Trop 2001;79:193)
Sites
  • In female genital tract, cervix is most commonly infected organ
Etiology
  • Schistosoma is a helminth and a Trematode (flukes)
  • Female genital tract is most commonly infected by Schistosome haematobium (Cytojournal 2012;9:15)
  • Other organisms include S. mansoni and S. japonica
Lifecycle of S.haematobium
  • When human skin gets exposed to contaminated water, the cercariae penetrate the skin and enter the blood stream
  • Then they enter the liver to mature into adult flukes
  • Later they migrate and reach the venous circulation of the urinary bladder and pelvis
  • Female flukes lay as many as 30 eggs per day, excreted through urine
  • The eggs release miracidia into the water, under optimal conditions
  • Miracidia infests Bulinus snail, an intermediate host
  • In the snail, infective cercariae are produced and released into water, to continue the cycle
Clinical features
Diagnosis
  • Optimal method of detection is direct examination of cervical tissue obtained by forceps biopsy through quantitative compressed biopsy technique (Am J Trop Med Hyg 2001;65:233)
  • Cytologic examination of cervical smears is not a reliable method to diagnose genital Schistosomiasis (Trop Med Int Health 2001;6:31)
Case reports
Treatment
  • Praziquantel (CDC)
Cytology description
  • Numerous inflammatory cells (eosinophils, lymphocytes and granulomas including multinucleated cells) are seen with ova
  • Viable ova measure 150 μ × 50 μm, and are surrounded by a thick shell
  • Egg of S. haematobium has a characteristic prominent terminal spine, while S. mansoni has a lateral spine and S. japonica is slightly oval with a rudimentary lateral spine
  • Ova in various stages of development may be seen
  • A few eggs may contain a miracidium, that have brightly eosinophilic cytoplasm and hematoxylin stained nuclei
  • Nonviable ova are empty with no internal structure; they may appear collapsed, shrunken, calcified, black or opaque
  • The smears may be bloody, secondary to extensive vascularization of cervix
  • If scattered ova are seen among numerous inflammatory cells, diagnosis may be challenging
Cytology images

Images hosted on other servers:
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S. haematobium - Pap

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With squamous cell
carcinoma - Pap

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Site unspecified: S. mansoni-lateral spine (left); S. japonicum (right)

Differential diagnosis