Mesocestoides (Cestoda) infection in children in the United States

BRIEF C L I N I C A L A N D LABORATORY OBSERVATIONS

Articles in this section should require 3 Journal pages or less; the text i,000 words or less. A combined total of 2 illustrations or tables with up to 10 reference~; will be accepted. An abstract is not necessary.

Mesocestoides (Cestoda) infection in children in the United States Yezid Gutierrez, M.D., Ph.D.,* John J. Buchino, M.D., and William K. Schubert, M.D., Cincinnati, Ohio A C C I D E N T A L INFECTIONS in m a n with Mesocestoides tapeworms have been reported I 1 times in Japan,"-" three times in the U n i t e d States, 3-' a n d once each in K o r e a ' a n d in Africa. s W e have studied the fourth Mesocestoides infection in a child in the u n i t e d States.

proglottids were excreted but no scolex was found. Six weeks later another strobila segment, 30 to 40 cm in length, was passed and discarded. Identification of the tapeworm was then made (Y.G.). Several months follow-up showed no proglottids or ova in the patient's stool.

CASE REPORT A 12-year-old white girl had been treated with piperazine (Antepar) six weeks previously because of "small worms" in the stools, but since they persisted she was referred to the Cincinnati Children's Hospital for evaluation. On admission, physical examination revealed a small, apparently normal child. Stools were consistently mushy, moderately guaiac positive, with numerous active tapeworm proglottids. Laboratory studies revealed a white blood count of 10,800/mm ~ with 28 polymorphonuclear leukocytes, 65 iymphocytes, 4 monocytes, and 3 eosinophils. Red blood cells were 4.54 million with slight hypochromia and occasional basophilic stippling. A hemoglobin concentration of 12.2 gm/dl, hematocrit 34.9%, serum iron 33.0 vg/dl, and total iron-binding cap:icity of 340 ttg/dl were interpreted as mild iron-deficiency anemia. Repeated stool examinations did not reveal parasite ov:i. There was no history of overseas travel or ingestion of any raw foods, though the paiient had been found often eating "garden dirt." The patient was treated twice with quinacrine (Atabrine) 50 nag orally and a saline enema, but vomited both times. Treatment was repeated through a nas0duodenal tube and numerous proglottids plus a 30 cm strobila segment were found in the stools, but no scolex. The anemia was treated with iron medication and the patient was discharged, to be followed by her private physician. One month later proglottids were again noted in the stools; she was readmitted and 140 mg of quinacrine was given. Many From the Department o f Pathologl; and Children's Hospital, University o f Cincinnati Medical Center. *Reprint address: Institute of Patholog); Case Western Reserve Uni~ersit); Cleveland 011 44106.

0022-3476/78/0293-0245500.30/0 9 1978 The C. V. Mosby Co.

See related article, p. 247.

The parasite. The total strobila measured 40 cm and was markedly shrunken because it ',,,'as fixed in formalin at room temperature. It was white, delicate, 1.31 mm in maximum width; the proglottids were barrel shaped toward the posterior end. Segments were stained with Semichon aceto-carmine a n d examined microscopically. Immature proglottids measured 0.5 mm in length by 1.06 mm in width. Mature proglottids (Fig. 1, A) had a well-developed excretory system, rudimentary parauterine organ, 51 to 56 testes, 50 to 60/t in dia~neter and located medially along the main excretory canals. Ovaries 165 by 56 It were slightly Iobulated with a V-arrangement posterior to the parauterine organ and the vitelline glands, 206.by 501t, were located posteiior to the ovaries. The genital pore was medial and ventral and the cin-us pouch was 125 x 62 tt (Fig. 1, A). Gravid proglottids (Fig. 1, B) measured 2.62 mm in length by 1.31 mm in width, the parauterine organ 200 • 400 V, and the egg mass 125 x 350/t. The vitelline glands and excretory canals were distinct but ovaries and testes were mostly ephased (Fig. I, B). The parasite is a cyclophyllidian tapeworm of the Mesocestoides genus, characterized by the parauterine organ and the medial genital aperture opening on the ventral surface. Species identification is not made since information on the genus taxonomy is scanty, and the above description is provided for future reference. DISCUSSION

poody

Mesocestoides is a u n d e r s t o o d group o f cestode parasites. T h e adult stage lives in the intestinal tract o f

171eJournalofPEDIATRICS

245

246

Brief clinical and laboratory observaHons

The Journal of Pediatrics August 1978

I~

Oo

E3 Fig. 1. Microscopic anatomy ofMesocestoides sp. A, Mature proglottid with medial genital pore (gp). Scale 0.5 mm. B, Gravid pr0glottid showing characteristic parauterine organ (po) with eggs. Scale 0.5 ram. dogs, cats, opossums, skunks, and foxes ~ (definitive hosts). The life cycle, not well known, apparently requires an arthropod '~ as first intermediate host and mice, snakes, lizards, or birds as second intermediate hosts) ~ In the latter, infective tetrathyridium larvae develop which upon ingestion grow to adults in the definitive hosts' intestine. Gravid proglottids are passed with the stools but eggs are usually not found. Species identification of Mesocestoides genus is difficult because, morphologic characteristics are variable, even within the same species.9 Voge ~ points out that several North American species of Mesocestoides are probably synonymous with M. variabilis, the most common species encountered in animals in this country. Moreover, 31. variabilis is very similar to 3L lineatus, which is found in animals in Europe an d perhaps in Asia. Including the present example, there have been 17 documented human infections of MesocestoMes. The Japanese cases ''~-occurred in patients over 30 years of age, and have been associated circumstantially with ingestion of raw blood and viscera of snakes (Elaphe quadrivirgata and Agkistrodon halys) for medicinal purposes. Epigastric pain and diarrhea were the chief complaints; eight of the patients were male, and the parasite was identified as ~L lineatus. The African report of a child less than 4 years of age mentions no symptoms; the infection was thought to result from consumption of raw partridge two months before proglottids appeared in the stools.8 The American infections occurred in children, one 5 years and three 12 to 14 months or age. -~-~'No clinical history was obtained in one instance; one Was asymptom-

atic; and one had "stomach ache and loss o f weight." The questionable mild iron-deficiency anemia o f our patient was not certainly related to the presence of the tapv.~,oi-m. All patients had proglottids in the stools. One infection each occurred in Texas, Missouri, New Jersey, and Ohio. The source of the infection is unknown, in spite of careful search in one previous ~ and in the present patient, but based on available Mesocestoides life cycle information, infection occurred from ingesting animal viscera with tetrathyridia larvae. The source is known or suspected in cases from abroad but in the American children it is only speculative and involves either accidental contamination of food, or ingestion o f infected material perhaps picked up in the yard. The parasite has been classified as 3L variabilis in three instances from this country ~-' and as Mesocestoides sp. in the present report. Gross superficial study of this tapeworm by the routine laboratory can lead to a misdiagnosis of either Dipylidiztm or Hymenolepis. Perhaps diagnosis would be more accurate if microscopic study of the specimen retrieved from patients were done by parasitologists. Moreover, i n all instances of Mesocestoides infection, careful search for the source should be undertaken. Quinacrine has been the most effective drug for Mesocestoides infections. Niclosamide* (Yomesan), widely used abroad in human infections with Taenia saginata, T.

solittm, Diphyllobothrium latum, ttymenolepis nana, H. *Niclosamideis availableto all licensedphysiciansthrough the Parasitic Disease Drug Service, Epidemiology Program, National Center for Disease Control,Atlanta, Ga. 30333, for use on patients over 2 )'ears of age.

Vohone 93 Nttmber 2

Brief clinical and laboratory observations

diminuta, a n d Dip)'fidium canin,m, has b e e n used in one J a p a n e s e a n d one A m e r i c a n Mesocestoides infection. REFERENCES 1. Kagei N, Kihata M, Shimizu S, Urabe M, and lshii A: The 10th case of human infection with Mesocestoides lineatus (Cestoda: Cyclophyllidea) in Japan, Jpn J Parasitol 23:376, 1974. 2. Morishita T, Nagase K, Moriyama K and Matumoto Y: The Ilth case of human infection with Mesocestoides lineatus in Japan, Jpn J Parasitol 24:353, 1975. 3 . Chandler AC: First case of human infection with Mesocestoides, Science 96:112, 1942. 4. Chandler AC: First record of a case of human infection with tapeworms of the genus Mesocestoides, Am J Trop Med 22:493, 1942. 5. Gleason NN, and Healy GR: Report of a case of Mesocestoides (Cestoda) in a child in Missouri, J Parasitol 53:83, 1967.

6.

7.

8.

9. 10. 11.

247

Gleason NN, Kornblum R, and Walzer P: Mesocestoides (Cestoda) in a child in New Jersey treated with Niclosamide (Yomesan), Am J Trop Med Hyg 22:757, 1973. Choi WY, Kim BC, and Choi HS: The first case of human infection with tapeworms of the genus Mesocestoides in Korea, Korean J Parasitol 5:21, 1967. Fain A, and Herin V: Notes h propos d'un cas d'infestation humaine par un Mcsocestoide ~t Astrida (Ruanda-Urundi), Pr6sence de ce cestode chez le chat et decouverte de larves du type Tetrathyridium ches divers v~rtebr~s, Ann Soc Beige Med Trop 54:893, 1954. Voge M: North American cestodes of the genus Mesocestoides, Univ Calif Publ Zool 59:125, 1955. Webster JD: Fragmentary studies on the life history of the cestode Mesocestoides latus, J Parasitol 35:83, 1949. Perera DR, Western KA, and Schultz MG: Niclosamide treatment of cestodiasis. Clinical trials in the United States, Am J Trop Med Hyg 19:610, 1970.

h fection of an infant with an adult Toxocara cati (Nematoda) C. Fordham yon Reyn, M.D.,* Thomas M. Roberts, Ph.D., Roger Owen, M.D., and Paul C. Beaver, Ph.D., Concord, N.H., Boston, Mass., Springl~eld, Vt., and New Orleans, La.

CAT AN D DOG ASCARIDS, Toxocara cati a n d Toxocara canis, p r o d u c e a s y n d r o m e in m a n k n o w n as visceral larva migrans. Infection is most c o m m o n in children w h o ingest e m b r y o n a t e d eggs in soil c o n t a m i n a t e d by pets. L a r v a e emerge in the h u m a n intestine, e n t e r the portal a n d p u l m o n a r y circulation, a n d produce fever, p u l m o n a r y infiltrates, hepatomegaly, a n d eosinophilia as they migrate. In m a n the larvea b e c o m e e n c a p s u l a t e d after several weeks or m o n t h s a n d eventually die; they d o not return via the bronchi a n d esophagus to the intestine to complete d e v e l o p m e n t as in their n o r m a l definitive hosts. 1"3 T h o u g h most Toxocara infections in h u m a n beings proceed only to the'larval stage, adult w o r m s h a v e occasionally been recovered from man. '-r W e report here a n infant infected with adult T. cati, discuss the relationshi p o f this infection to VLM, a n d e m p h a s i z e the p o t e n t i a l

From the Division of Infectious Disease, Department of Medichte, Beth lsrael Hospital; the Department of Tropical Public lteahh, llarrard School of Public tIealth; the SpringfieM Hospital; and the Department of Parasitolog), Tulane University School of Medicbw. *Reprint address: Concord Clinic, 279 Pleasant St., Concord, Nil 03301.

0022-3476/78/0293.0247S00.30/0 9 1978 The C. V. Mosby Co.

confusion o f this h e l m i n t h With i m m a t u r e Ascaris htn~bri-

coides. See related article, p. 245.

Abbreviation used VLM: visceral larva migrans C A S E REPORT In December, 1976, an 8-month-old girl from Vermont was brought to her pediatrician after her mother found a small live worm partly protruding from the child's anus. Except for an episode of pneumonia at age 2 weeks the child had been in good health. No systemic, pulmonary, or visual symptoms were reported. Physical examination was normal. A white blood count, taken two days later, when the child sustained a traumatic femoral fracture, was 13,300 mm 3 with 1% cosinophils; a stool examination was negative for parasites. Based on its gross appearance, the pediatrician thought the worm was an immature A. honbricoides and treated the child with pyrvinium pamoate, 110 mg by mouth in a single dose. No additional worms were passed. Further investigation revealed that the worm was an adult female Toxocara cati, 71 mm long and i.4 mm at its widest point,