Ascaris Lumbricoides Eggs inVaginal Wet Smear

Dear Dr. Bedrossian:

The primary function of the clinic-based vaginal wet

mount smear test is immediate and accurate reporting of

abnormal vaginal flora, including motile trichomonads,

fungal hyphae, and clue cells for the diagnosis of Bacte-

rial vaginosis. Other disease processes can rarely be iden-

tified by this test, including parasites other than trichomo-

nads.1–3 We report a case of the nematode, eggs of asca-ris lumbricoides, observed in vaginal wet smear from a

woman who attended Institute’s endocrine infertility clinic

for investigations and management of her primary infertil-

ity. We also review briefly, previous reports of parasites

other than trichomonads that have been identified in vagi-

nal wet smears.

A 32-yr-old woman was referred to the Institute’s endo-

crine infertility clinic for the investigations and manage-

ment of her primary infertility of 3 yr and 6 months dura-

tion. Her menstrual cycles were regular and normal. On

physical examination, the woman was found to be healthy,

with a BP 120/80 of mm Hg. Her per-speculum examina-

tion revealed excessive white discharge and mild conges-

tion of the cervix. A wet smear was prepared from vaginal

discharge and examined under light microscope. The wet

smear preparation revealed many squamous epithelial cells,

intermediate cells, Doderlein bacilli, cocci, polymorphonu-

clear-leukocytes, occasional erythrocytes, and 5–6 eggs of

ascaris lumbricoides in different fields. The eggs were

identified by their round to oval shape, 70l 3 40l in size,

with a thick crescent form outer membrane. The visible

interior features, including the centrally placed unseg-

mented ovum containing yolk sack granules, were typical

of Ascaris lumbricoides eggs (Figure 1). These observa-

tions provide the first conclusive evidence of the presence

of eggs of A. lumbricoides in vaginal wet smear.

Worm infestation is world wide, the incidence is particu-

larly high among children and in the lower socio-economic

groups. According to the World Health Organization

(WHO) report (1995), 250 million persons are infected

with A. lumbricoides and 60,000 persons die from ascaria-

sis each year.4 A. lumbricoides is a cosmopolitan nematode

with a life cycle involving one host only. It can live in the

human bowel for many years without causing any symp-

toms, or cause abdominal pain, nausea, malnutrition, and

even perforation of gut. Unripe eggs passed in feces subse-

quently become infective embryonated eggs. Infection is

transmitted by feco-oral route. In the present case, routine

Papanicolaou stained cervical smears were collected on the

same day as wet smear examination, and microscopic stool

examination was carried out within 4 days, both did not

reveal any evidence of worm infestation. The presence of

parasites other than trichomonads in cervico-vaginal speci-

Financial Disclosure: The authors have no connection to any compa-nies or products mentioned in this letter.

*Correspondence to: Bapurao N. Mali, M.Sc., Ph.D., Research Officer,National Institute for Research in Reproductive Health (ICMR), JehangirMerwanji Street, Parel, Mumbai – 400 012, India.E-mail: dirirr@vsnl.com

Received 0; Accepted 0DOI 10.1002/dc.20425Published online in Wiley InterScience (www.interscience.wiley.com).

Fig. 1. High magnification of egg of A. lumbricoides in vaginal wetsmear shows details of its internal structure, with a thick crescent formouter membrane (Vaginal wet mount smear 3450). [Color figure can beviewed in the online issue, which is available at www.interscience.wiley.com.]

' 2006 WILEY-LISS, INC. Diagnostic Cytopathology, Vol 34, No 5 387

men sometimes correspond to the local or systemic symp-

toms, but it is very difficult to know the accuracy of this

finding. Follow-up testing with stool and blood examina-

tion can often be negative, as observed in the present case.

Even when this is so, it seems risky to dismiss the organ-

isms as contaminants, as stool testing itself is not very sen-

sitive. Although the presence of eggs of A. lumbricoides inthe vaginal wet smear may be due to contamination, its

observation in the wet smear proved the usefulness in

determining worm infestation in this woman, which is

often asymptomatic. Treatment based on wet-smear screen-

ing, correlated with relevant symptoms, can help clinicians

for diagnosis and appropriate treatment, as only symptoms

and naked-eye evaluation of the vagina and its discharge

are poor indicators for determining the etiology of vulvo–

vaginal infections.5

After an extensive literature search using the following

medical subject headings: vaginal wet smear and vaginal para-

sitosis, cervical smear and vaginal parasitosis, and Papanico-

laou smear and vaginal parasitosis additional potentially rele-

vant studies were identified from the references obtained. No

attempt was made to identify unpublished studies or studies

only presented in conference abstracts. We identified only two

previous case reports in which parasites other than trichomo-

nads have been reported in the vaginal wet mount smear prep-

aration viz Enterobius vermicularis2 and Schistosomiasis.3 To

add to this list our finding provides the first documentary evi-

dence for the presence of Ascaris lumbricoides eggs in vaginalwet smears. The scanty published reports on the subject ‘‘vagi-

nal wet smear and parasites other than trichomonads’’ indi-

cates the infrequent utilization of wet smears for the identifica-

tion of abnormal vaginal flora in the routine gynecologic prac-

tice6,7 compared with the extensive use of Papanicolaou

stained cervico-vaginal smear for cervical cancer screening,

which presents a variety of parasites other than trichomonads.8

The presence of A. lumbricoides eggs in Papanicolaou stained

cervico-vaginal smear have been reported in four case

reports.9–12 All these case reports are from India, and except in

one case report,12 all9–11 are from the same place.

Thus, a variety of parasites other than trichomonas vag-inalis, which are not usually sexually transmitted, may be

present in the human vagina and can be detected in ‘‘Pap

specimen.’’ Although it is very difficult to know how they

were picked up in ‘‘Pap specimen,’’ their evidence based

detection provides an opportunity for early treatment in

asymptomatic women. We emphasize here, to remain

aware of rare parasites, besides T. vaginalis, in vaginal

wet mount smears.

Acknowledgments

The authors acknowledge Dr. C.P. Puri, Director, National

Institute for Research in Reproductive Health, for his sup-

port. The authors also thank Mrs. Shanti Ganeshan,

Library and Information Officer, for her contribution to

the literature search and Mrs. Akanksha Dalvi for her sec-

retarial assistance. This institute is supported by Indian

Council of Medical Research, New Delhi – India. Ref.

No. (NIRRH/MS/1/2005).

B.N. Mali, M.Sc., Ph.D.*

Kamal T. Hazari, M.D., D.G.O.

Division of Clinical Research

National Institute for Research in Reproductive Health

Parel, Mumbai, India

Pervin K. Meherji, M.D, D.G.O., Ph.D.

Division of Endocrine Infertility

National Institute for Research in Reproductive Health

Parel, Mumbai, India

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5. Schaaf VK, Perez-Stable EJ, Borchardt K. The limited value ofsymptoms and signs in the diagnosis of vaginal infection. ArchIntern Med 1990;150:1929–1933.

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8. Stelow EB, Pambuccian SE, Bardales RH, Cartwright CP, Reif CJ,Stanley MW. Loa loa presenting in a thin-Prep Pap test: case reportand review of parasites in cervico-vaginal cytology specimens.Diagn Cytopathol. 2003;29:167–171.

9. Mali BN, Joshi JV. Vaginal parasitosis. Acta Cytol 1987;31:866–868.

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