Contents << Previous Chapter Next Chapter >> Search

The most common medical helminthes, which are of dermatological interests, associated with skin manifestations are:


Oxyrius, Necator Americans, Ancylostoma duodenale, Strongyloidesa and larva migrans.

Tissue round worms : Filariasis , Loasis and Dracunculosis .


Taenia solium and Echinococcus granulosum.


Visceral Schistosomiasis and cutaneous Schistosomiasis.



(Thread worm, pinworm, Entrobius vermicularis)

 Pinworms are the commonest of the human helminthes affecting mainly children.

Fig. 153. Ova of entrobius vermicularis

Infestation is due to ingestion of food or drinks contaminated with the eggs of the parasite or via infested fingers. The eggs mature in the rectum where after two weeks the eggs hatch and the female migrates out of the anus especially at night to lay more and more eggs .

During its migration, it causes intense itching, where by scratching the eggs may be carried under the nails or on the finger to cause a common way for re-infection.

Methods of Infestation

Ingestion of the nematode eggs, most commonly carried by finger nails contaminated during scratching the anal area.

Infested dust, in which eggs may survive for up to 13 days.

Clinical Features

Skin manifestations

Skin excoriation and urticarial lesions.

Nocturnal pruritus: anal , vaginal and perineal itching at night which may be severe causing sleep disturbances and irritability.

Perineal intertrigo, secondarily infection and nocturia due to severe itching vulvar irritation and mucoid discharge.

General manifestations

Peritonitis and salpingitis are rare complications .

Other symptoms are irritability , insomnia and enuresis .


Peri-anal itching and the detection of worms in the stool are diagnostic.

Scotch tape is fixed on the peri-anal area better in the morning then removed and mounted on a glass slide and examined by the low power microscope may show the ova of the worm.


General measures

General hygiene - the children should be instructed to wash their hands thoroughly after using the toilet and before eating.

Keeping the nails shortly cut.

General hygiene for the bed linen, toilets and houses to eradicate the ova. Changing the underwear and bed linens. Boiling of suspected clothes and linens at least during treatment.

The bedroom vacuum is cleaned especially if the floor is covered with carpets.

Specific treatment

Piperazine citrate (Antepar) is the drug of choice. This is given in single daily dose of 65 mg./kg. body weight or one large single dose (not exceeding 2500 mg.), taken one hour before breakfast mixed with Senna for eight consecutive days is very effective . The drug is safe but should not be given in renal impairment or uncontrolled cases of epilepsy.

Piperazine 100 mg/kg and (Pyrantel pamoate) 10 mg/kg are also effective.

Mebendazole is an effective drug given in a single dose of 100 mg . In case of re-infection treatment is repeated after two weeks giving 100 mg. Mebendazole twice daily for three consecutive days .

Pyrivinium pamoate (Povan-Park-Davis ) is given in a single dose of 5mg./kg.of body weight. This can be repeated after one week . It should be noted that the stools during using the medication becomes bright red.

Thiabendazole (Mintezol Merck - Sharp & Dohme): The dose is 25mg.//kg. body weight given in two equal doses in one day and can be repeated after one week .

Antihistamine syrup may be needed to relieve severe distressing itching. Topical steroid cream can be used if itching is severe and persistent .


(Medina, Guinea worm)

Dracunculosis is a chronic infestation due to the nematode, Dracunculus medinensis. Dracunculus medinensis, Guinea worm or Medina worm is a thread worm where the female may reach a length of more than one meter. The disease occurs in India, West Africa in East and Central Africa , Saudi Arabia, Yemen, Iran, Pakistan and the West Pacific. Infestation occurs by drinking water contaminated with a small crustacea belonging to the genus Cyclops (water fleas ) .

The adult female worm matures over a period of one year in man and discharges larvae through an ulcerated skin lesion. Thousands of these larvae are produced, particularly when the ulcerated area becomes on contact with water; these survive for 3-4 days and can develop further in water fleas (Cyclops) .

Modes of infestations

Infestation of man follows drinking water usually from wells, containing infested Cyclops species, the larvae are released and penetrate the intestine. Further maturation occurs in the retroperitoneal space or other sites where mating occurs after about 3 months and the males subsequently die.

The females grow and migrate downwards, usually to the lower limbs. The female penetrates the skin of the leg and can then discharge larvae after exposure to water.

When the leg is immersed in water a milky fluid loaded with the larvae is ejected, where after complete ejection of the larvae the worm dies. The Cyclopes ingest the ejected larvae where larvae complete their life cycle there.

Clinical Manifestations

General manifestations

Constitutional symptoms are usually mild and begin when the larvae begin to migrate to the skin. The general manifestations are mild fever, headache, malaise and gastrointestinal disturbances.

Skin manifestations

Skin lesions are in the form of papule at the site of the worm under the skin, which becomes a vesicle and a large bulla, which ulcerates, where the head of the worm may be seen in the ulcer as a tortuous thread like .

Fig.154b. Dranculosis : multiple papules,vesicles and ulcerations.

Generalized urticaria and mild itching are common. All the general manifestations may subside after ulceration of the skin and the worm begins to extrude their larvae.

Secondary bacterial infection of the ulcer may cause more destruction to the tissues.


General measures:

Supplying fresh water, cleaning, and disinfecting wells from Cyclopes.

Fig. 154. Medena Worm lesion

Boiling water in endemic areas may kill Cyclopes .

Specific treatment

The treatment of choice is injection of Phenothiazine in olive oil emulsion usually kills the worm .

Much care should be considered in order not to pull it too hard which may cause unwanted separation of the worm leaving a retained part in the subcutaneous tissue .

Benzimidazole oral preparations such as Metronidazole given daily for about one week, which can kill the worm, which then extracted gently through the skin .

Traditional method of treatment

The natives in the endemic areas has their own traditional way to get red of the worm:

As soon as a part of the worm becomes apparent through the skin surface, the infested leg is immersed into water for some time .

The worm extends more of its body in the presence of water .

The patient has an experience to pull gently the extruded part and rewinds it on a stick. He repeats this procedure daily cautiously and with great care and patience till complete extraction of the worm .



Schistosomiasis is a serious systemic disease, which is caused by different species:

Schistosomes or blood flukes: Rashes may occur during the invasive stage of the disease after penetration of the skin or the mucous membranes by cercaria. The skin is being penetrated by cercaria, and later there may be skin involvement at or near mucocutaneous surfaces and less commonly at more distant sites on the trunk, following dissemination of ova.

A second group of non-human Schistosomes cause cutaneous symptoms only. "Swimmers itch" or cercarial dermatitis is an example of this type.

A. Skin manifestations of Cutaneous Bilharziasis

  1.  Schistosome Dermatitis

    Schistosome dermatitis is due to invasion of the cercaria in to the skin during swimming or wadding in water.

Clinical Picture

Itching and transient erythema after the bather leaves water which decreases after few hours to recur again .

Fig. 155. Biharzial granuloma

Erythematous macules and papules appear on areas immersed in water. The condition may last for few days where spontaneous recovery is usually the rule.


Mild cases need no treatment .

Antihistamines and topical steroid may be required to relive itching.

Rubbing and drying the skin by a towel may relieve the itching .

  1.  Urticarial reactions: in the early weeks of the disease

    Urticaria lesions usually develop after penetration of the skin by cercaria. Urticaria may be severe and called sometimes urticarial fever.

  1.  Paragenital granuloma and fistulous tracts.

    This may begin with mild symptoms such as itching and erythematous macular or papular eruption due to penetration of the cercaria to the skin from contaminated water sources. The symptoms usually disappear after a short time. Few years later the manifestations are more severe due to involvement of the internal organs and the skin .

    Late skin manifestations are in the form of urticaria, ulceration of the skin and bilharzial granuloma mainly on the external genitalia, which is cauliflower like vegetation. A hard nodular or plaque type of bilharzial granuloma may appear also on the trunk that becomes darkly pigmented and scaly.

  1.  Ectopic cutaneous Schistosomiasis.

    Ectopic sites of egg deposition probably arise through migration of adult worm via the paravertebral venous plexus.

    Skin involvement may occur either as a result of the initial penetration of the skin by water-borne free living cercaria or in the later stages of infestation following ectopic localization of worms or ova.

    In ectopic cutaneous Schistosomiasis the ova may become deposited in the skin as well as in other ectopic sites such as conjunctiva, trunk, lungs and central nervous system.

    The periumbilical area is a common site but other areas may be involved. In some cases, the lesions have a segmental or zosteriform distribution.

Clinical features of Ectopic Bilharziasis

The primary lesion is a flesh-colored, ovoid , firm papule reaching a size of 2-3 mm. These papules form slightly raised plaques with irregular contours and mammillated surface.

The skin over old nodules may become deeply pigmented, scaly, and may later ulcerates. Hypopigmented patch may develop after healing.

B. General manifestations of bilharziasis

Fever, purpura, malaise, arthralgia, abdominal cramps, and diarrhea .


The symptoms resolve in about 4-6 weeks.

C. Systemic manifestations of bilharziasis

Liver cirrhosis

Intestinal involvement .

Urinary tract involvement

Kidney and bladder infection, which may lead to carcinoma of the bladder. Heart, central nervous system and retina may be infested with the protozoa.

Treatment of Bilharziasis

Preventive measurers:

Prevent contact of human excreta from coming in contact with water. Eradication of snails.

Specific measures :

Tarter emetic or Stibophen , Triostan and Astiban all are different medications used for treatment of bilharziasis .

Niridazole ( Ambilhar) is also very effective drug .



Amoebiasis is a very common disease caused by Entemeba histolytica. The disease is endemic in all warm and temperate parts of the world with low standard of living and low sanitary conditions .

The prognosis is serious in neglected case particularly in infants.

Clinical Manifestations:

Amoebic dysentery - this is due to invasion of the trophozoites to the mucosa of the large intestine .

Metastatic lesions - these are blood born due to escape of amoebae from the bowel to blood stream causing metastatic abscesses particularly in the liver.

Skin lesions:

Most of the lesions begin as deep abscesses, which rupture and form ulcerations with distinct raised , cord-like and thickened edges , surrounded by an erythematous halo . The base of the ulcer is covered with necrotic tissue and hemopurulent pus in which amoebae are present.

Cutaneous Amoebiasis develops when invasive amoebae escape from the bowel to skin mainly on the trunk, abdomen, external genitalia and buttocks.

Cutaneous Amoebiasis can spread very rapidly and may terminate fatally, so early diagnosis and treatment is important.

A solitary lesion may be mistaken for an epithelioma, tuberculosis and verrucosa cutis.

Mucous membrane lesions

Mucous membranes may be involved when amoebae are implanted in the mucosa, most commonly that of the vagina, cervix uteri or glans penis and rarely in the mouth.


  1.  Fresh smears :

    Examination of fresh material from the cutaneous lesion regularly discloses amoebae. Material should be taken from the edge of the ulcer avoiding necrotic tissue, and examined at once under the microscope. The demonstration of motile trophozoites containing red blood cells is diagnostic.

  1. Serological tests:

    Are helpful for rapid screening especially in school children.

  1.  Serial stool examinations should be performed.


Metronidazole. The recommended adult dose is 800 mg orally three times daily for 10 days. This may be combined with Diloxanide furoate 500 mg three times daily or followed by oral Diiodohydroxyquin, 650 mg three times daily for 21 days, to eliminate intestinal cysts.

Local cleaning of cutaneous ulcers with antiseptic solutions may be necessary.

Hepatic abscess needs to be drained, this is most safely done by needle aspiration.

Effective treatment is usually followed by complete healing of the skin lesion without any need for plastic surgery.



Trichomonas vaginalis is a disease of adults but due to direct or indirect infection of young ages , it is included briefly in this chapter .

Trichomonas vaginalis is found worldwide affecting all races, but more common in Negroes.Although infection is commonest in the second and third decades, young age even babies may be infected .

Many adults are asymptomatic carriers - particularly males. It can be isolated from up to 15% of men with non-specific urethritis.

Discharge in males is scant.

Modes of Infection

Direct infection during sexual intercourse .

Indirect infection: babies and young children may be infected from infected parents .

The condition is frequently associated with gonorrhea .

Occasional non-sexual transmission has been reported.

Fig. 156. Trichomonas vaginalis organism

Clinical Manifestations:

The organism invades the vagina and urethra in women, causing vaginitis and vulvitis with a characteristic pale yellow frothy discharge. Trichomoniasis characteristically causes a copious discharge with vaginal soreness or irritation and urinary frequency.

The odor of the discharge is often unpleasant although this feature is not specific. In many cases bubbles can be seen in the discharge . The vaginal mucosal and cervical surfaces are infested and sometimes covered with punctate hemorrhages.

Vulva soreness and pruritus with inflammation of the surrounding skin are common, whereas infection of Skenes or Bartholin's glands with abscess formation rarely occurs.

In males the condition occurs with non-specific urethritis in up to 5% of cases, and balanitis may also occur.The organism may be harbored in the prostate without symptoms.


Standard treatment for adults is with Metronidazole 400 mg twice daily for 5 days.

Single dose treatments (four tablets, 500 mg.) can be given as a single dose is also effective.

Simple douching may relieve vaginal symptoms (20-ml vinegar to one liter of warm water).



Creeping eruption is a skin eruption, caused mainly by the larvae of hookworm Ancylostoma Brazilians and to a lesser extent by other larvae as that of Ancylostoma Cranium, horse bottle fly or larvae of strongyloides that penetrate the skin during walking barefooted especially in children. The commonest sites involved are feet, buttocks, genitalia and hands.

The condition is common in all warm climates.

Modes of Infection

Adult hookworms live in the intestines of dogs and cats and the ovae are deposited in the animals feces.

Under favorable conditions of humidity , warm and in sandy , shady areas, hatching of the ova into infective larva which can penetrate human skin.

Infections are acquired by children in sandpits, plumbers under houses, farm-workers under outbuildings, hunters in hides, gardeners from the soil and sea bathers from the sandy shore above the ebb and flow of the tides.

Clinical Picture

Mild itching at the site of penetration of the larva into the skin. Later itching becomes more severe with excoriation and secondary infection to the sites.


                                                                       Fig.156b.Creeping eruption

Tortuous thin, red lines are formed along the way where larvae migrate into the skin. This line is interrupted by small papules where the larvae hide in.

These larvae may be removed from the skin during severe itching and may be detected under the fingernails.

Some cases of creeping eruption may show patchy infiltrate of the lungs with Eosinophils (Loeffler‘s syndrome).


Symptomatic : Antihistamines orally and mild topical steroid to combat severe itching .

Antibiotics in cases complicated by secondary bacterial infection .

Freezing of the larvae by ethyl chloride spray is an old and effective.

Thiabendazole (Mintezole-Merk Sharp & Dohme) :

Dose 25mg. twice daily for two successive days .

The treatment of choice is the topical application of 10% Thiabendazole.

Either the commercially available oral preparation may be used directly, or two 0.5 g tablets of Thiabendazole are triturated in 10g petrolatum, and applied twice daily, where 95% of the tracks clear within a week. Oral Thiabendazole is less effective and more toxic.

Albendazole 400 mg daily by mouth for 3 days is safe and often effective.



"Ground itch," "dew itch" is an eruption mainly on the soles, interdigital spaces and ankles due to skin penetration by larvae of the hookworms Ancylostoma duodenal, Necator Americans, and the roundworm Strongyloides stercoralis.

The disease is prevalent in tropical and subtropical areas.

Clinical Picture

Constitutional symptoms: are more severe in children such as anemia debility ,lack of concentration , circulatory , nervous and digestive disturbances.

Skin manifestations : appear 2-3 months before the systemic involvement by the hookworm .

Skin lesion: Erythematous macules and papules appear at the site of penetration of the larvae into the skin. Later vesicles, pustules and ulceration are formed .

The ulcer is indolent, irregular with rounded slightly elevated edges covered with necrotic purulent exudate.Severe itching and urticarial lesions may occur during the course of the disease where later the skin becomes pale or earth color.

Diagnosis: Detection of the ova of the hookworm in the feces.


Tettrachloroethylene: for Necator Americans. Children dose is - 0.06 cc per pound of weight while adult dose is 5 cc given with skimmed milk. Fats and oils should be avoided . No need for purgation.

Thiabendazole: is also effective .

It should be noted that if ascaris coexist with ancylostoma , ascaris should be treated first with Alcopar before using Tetrachloroetheylene.


(Hookworm Disease)

The adult worms live in the jejunum with the head firmly attached to the mucosa and cause bleeding. Bleeding leads to anemia, hypoproteinemia, digestive disturbances and retarded development. Thousands of eggs are passed in the feces, which can resist dryness.

Under favorable conditions of warmth and humidity, eggs are hatched into motile rhabditiform larvae. After 5 days and further they molt into infective filariform larvae. They migrate upwards through soil and grass, and after a period of contact with human skin, the larvae penetrate the skin.

Walking barefoot is the commonest method of infection. Favorable places for transmission include soil around houses such as plantations, cultivated fields, and mines.

Clinical Manifestation

After penetrating the skin, larvae migrate within a day or two via the blood stream to the lungs, pass up the bronchial tree where they are swallowed and pass down to the esophagus, reaching the duodenum and jejunum. These mature in 4-6 weeks.

In passing through the lungs they cause acute alveolitis or pneumonitis.


Diagnosis can be reached by:

  1.  Clinical manifestations.

  2.  Pneumonitis seen radiologically (characterized Leoffler‘s syndrome).

  3.  Eosinophilia

  4.  Diagnosis can be confirmed by detection of the characteristic eggs in the feces.


Ground itch is treated symptomatically, with an antipruritic cream such as crotamiton and 1% hydrocortisone.

Oral antihistamines.

Pulmonary symptoms, if severe, respond to corticosteroids.

Established infections respond to a three day course of Albendazole or Mebendazole

Oral iron is given for iron deficiency anemia .



  1. Elgart ML. Onchocerciasis and dracunculosis. Dermatol Clin 1989; 7: 323-30. Morbidity and Mortality Weekly Report. Regional workshop on dracunculiasis in Africa. MMWR 1987; 35: 797.

  2. Watts SJ. Dracunculiasis in Africa in 1986: its geographic extent, incidence and at-risk population. Am J Trop Med Hyg 1987; 37: 119-25.

  3. Broadbent V. Children‘s worms. Br Med J 1975; i: 89. Pearson RD, Irons RP, Irons RP Jr. Chronic pelvic peritonitis due to the pinworm Enterobius vermicularis. J Am Med Assoc 1981; 245: 1340-1

  4. Burke JA. Strongyloidiasis in childhood. Am J Dis Child 1978; 132: 1130-6. von Kuster LC, Genta RM. Cutaneous manifestations of strongyloidiasis. Arch Dermatol 1988; 124: 1826-30.

  5. Katz R, Ziegler J, Blank H. The natural course of creeping eruption and treatment with thiabendazole. Arch Dermatol 1975; 91: 420-4.

  6. Beaver PC, Jung RC, Cupp EW, eds. Clinical Parasitology, Philadelphia: Lea & Febiger, 1984: 340.

  7. Davis A. Recent advances in Schistosomiasis. Quart J Med 1986; 58: 95-110. El-Zawahary M. Schistosomal granuloma of the skin. Br J Dermatol 1965; 77: 344-5.

  8. Gonzalez E. Schistosomiasis, cercarial dermatitis and marine dermatitis. Dermatol Clin 1989; 7: 291-300.

  9. Mahmoud AAF, ed. Schistosomiasis. In: Clinical Tropical Medicine and Communicable Diseases. London: Bailliere Tindall, 1987.

  10. Mahmoud AAF. Praziquantel for the treatment of helminthic infections. In: Stollerman GH, ed. Advances in Internal Medicine 32. Chicago: Year Book Medical Publishers, 1987: 419-34.

  11. Torres VM. Dermatological manifestations of Schistosomiasis mansoni. Arch Dermatol 1976; 112: 1539-42.

  12. World Health Organization. Atlas of the global distribution of Schistosomiasis. Parasitic Diseases Programme. WHO, 1987, Geneva.

  13. Baird JK, Wear DJ. Cercarial dermatitis. The swimmers itch. Clin Dermatol 1987; 5: 88-91.

  14. Bernhardt MJ, Mandojana RM. Sea bathers eruption. Clin Dermatol 1987; 5: 101-2.

  15. Hoeffler DF. Swimmers itch. Cutis 1977; 19: 461-7.Medical Letter. Drugs for parasitic infections. Med Let 1988; 30: 15-24.

  16. Fujita WH, Barr RJ, Gottschalk HR. Cutaneous amoebiasis. Arch Dermatol 1981; 117: 309-10.

  17. Martinez-Palomo A. The pathogenesis of amoebiasis. Parasitol Today 1987; 3: 111-18.

  18. Knight R. The chemotherapy of amoebiasis. J Antimicrob Chemother 1980; 6: 577-93.

  19. Fouts AC, Kraus SJ. Trichomonas vaginalis. Reevaluation of its clinical presentation and laboratory diagnosis. J Infect Dis 1980; 141: 137-52.

  20. Honigberg B. Trichomonads of importance in human medicine. In: Kreier JP, ed. Parasitic Protozoa 2. New York: Academic Press, 1978: 275-86.

  21. Lossick JG. Treatment of Trichomonas vaginalis infection. Rev Infect Dis 1982; (Suppl.): S801-8.

  22. Foulkes JR. Human trypanosomiasis in Africa. Br Med J 1981; 283: 1172-4.

  23. Greenwood BM. African trypanosomiasis. In: Weatherall DJ, Ledingham JGG, Warrell DA, eds. Oxford Textbook of Medicine 2nd edn. Oxford: Oxford University Press, 1987.

  24. Gallerano RH, Marr JJ, Sosa RR. Therapeutic efficacy of allopurinol in patients with chronic Chagas‘ disease. Am J Trop Med Hyg 1990; 43: 159-66.


Contents << Previous Chapter Next Chapter >> Search