CHAPTER 20: PARASITIC INFESTATION Flashcards
May be the sole manifestation of early amebiasis
Chronic urticaria
Treatment of choice for amebiasis cutis
Metronidazole 750mg TID x 10 days
Common cause of vaginal pruritus with burning and frothy leukorrhea
Vaginal mucosa is bright red with pseudomembranous patches
Trichomoniasis
Treatment of trichomoniasis
Metronidazole 2g single dose
Or 500mg BID x 7 days
Treatment for trichomoniasis in pregnant women
Clotrimazole 100mg intravaginally per night x 2 weeks
Treatment for cutaneous leishmaniasis
Spontaneous healing in 12-18 months
Topical: paromomycin sulfate 15% + methylbenzethonium chloride 12%
Ketoconazole cream
Cryotherapy, photodynamic therapy, laser
Systemic: immunosuppressed
Sodium antimony gluconate IM/IV 20mg/kg/day in 2 doses x 28 days
Cutaneous ulcer
Transmitted by sandfly
Endemic in Asia minor and Mediterranean
Cutaneous leishmaniasis
The vector hosts of old world cutaneous leishmaniasis?
for New World cutaneous leishmaniasis?
VECTORS:
Phlebotomus sandflies:
Old World type
Phlebotomus perniciosus and Lutzomyia sandflies: New World cuta- neous leishmaniasis.
Mucocutaneous leishmaniasis has an initial cutaneous ulcer and develops a secondary mucosal lesions after how much time?
Within 5 years
Earliest mucosal lesion in mucocutaneous leishmaniasis
Hyperemia of nasal septum with subsequent ulceration
aka ESPUNDIA
mucocutaneous leishmaniasis
Antimony resistance is common in this type of leishmaniasis
mucocutaneous leishmaniasis
Treatment for mucocutaneous leishmaniasis
Combination therapy:
Antimonials with rifampin/azithromycin
Amphotericin B
aka kala-azar, dumdum fever
Visceral leishmaniasis
Primary target site of leishmanial parasites in visceral leishmaniasis is
Reticuloendothelial system
-spleen, liver, bone marrow and lymph nodes
Etiologic factors causing visceral leishmaniasis
Leishmania donovani spp. donovani, infantum, and chagasi
Treatment for visceral leishmaniasis
Pentavalent antimony
Amphotericin B- resistant cases
Evanescent erythema, erythema multiforme and edema (angioedema) are the early skin manifestations observed in
Trypanosomiasis
causative agent of african trypanosomiasis?
Trypanosoma gambiense and T. rhodesiense in Africa
causative agent of AMERICAN trypanosomiasis?
T. cruzi
Chagas’ disease
reduviid bug (kissing bug, assassin bug),
Romana’s sign
American trypanosomiasis (Chagas’ disease)
Treatment of East African (Rhodesian) trypanosomiasis
No CNS involvement:
With CNS involvement:
No CNS involvement: suramin
With CNS involvement: melasoprol
Treatment for West African (Gambian) trypanosomiasis
Pentamidine isethionate
Treatment for American trypanosomiasis (Chagas disease)
Nifurtimox
Benznidazole
Treatment of toxoplasmosis
Pyrimethamine and sulfadiazine
Organisms enter a snail
Swimming
Attack by burrowing into skin
Transient erythematous reaction then recur after 10-15 hrs
swimmer’s itch or
Schistosome cercarial dermatitis
Mild itching and papular dermatitis of feet
Urinary bladder/ intestinal inhabitation of the organisms
Fever, chills, pneumonitis, eosinophilia, petechiae, malaise, abdominal crsmps, arthritis, liver spleen involvement
Visceral schistosomiasis (bilharziasis)
A severe urticarial eruption known as urticarial fever or Katayama fever is frequently present along
S. japonicum infection;
Treatment of schistosomiasis
For both S. haematobium and S. mansoni, praziquantel (Biltricide), 40 mg/ kg orally for each of two treatments in 1 day, is the therapy of choice.
S. japonicum treatment requires 60 mg/kg in three doses in 1 day
Painless nodules in subcutaneous tissues
Organisms may enter general circulation and form cysts in striated muscles
Cysticercosis cutis
tx for Cysticercosis
Albendazole or praziquantel
Also known as hydatid disease
From ova-contaminated feces from an infected dog
Infestation of liver and lungs
Eosinophilia, intractable urticaria and pruritus
Echinococcosis
tx for Echinococcosis
praziquantel
Chief symptom of pinworm infestation
nocturnal pruritus ani
Oxyuriasis is caused by
roundworm Enterobius vermicu- laris,
Treatment of enterobiasis
Albendazole, 400 mg, or
mebendazole, 100 mg, or
pyrantel pamoate, 11 mg/kg (maximum 1 g), given once and repeated in 2 weeks, is effective.
Personal hygiene and cleanliness at home are important.
Erythematous macules and papules that turn into vesicles
Occurs in toe webs, soles and ankles
Iron deficiency anemia, skin becomes dry and pale or yellowish
Carried into circulation to the lungs—pharynx—swallowed into the small intenstine
Hookworm ( ancylostoma, necator)
Treatment of hookworm disease
Albendazole 400mg single dose
Mebendazole 100mg BID x 3 days or 500mg single dose
Pyrantel pamoate 11mg/kg (max 1g) OD x 3 days
Prevention of contamination of soil
Treatment for hookworm disease
Albendazole 400 mg SD
Mebendazole 100 mg BID x 3 days or 500 mg SD
Pyrantel pamoate 11 mg/kg ( max 1 g) OD x 3 days
Prevention of contamination of soil
Term applied to twisting, winding linear
skin lesions produced by the burrowing of larvae.
Creeping eruption (larva migrans)
(Hookworm: ancylosytoma braziliense or ancylostoma caninum)
patchy infiltrate of the
lungs and eosinophilia as high as 50% in the blood and 90%
in the sputum, may complicate creeping eruption.
Loeffler syndrome
Tx for larva migrans
Ivermectin, 200 µg/kg, generally given as a single 12-mg dose and repeated the next day, or
albendazole, 400 mg/day
for 3 days, is an effective treatment.
autoinfection caused by penetration of the perianal skin by infectious
larvae as they are excreted in the feces.
Aka peri-anal larva migrans syndrome
Caused by strongyloides stercoralis
Larva currens
Tx for larva currens
ivermectin, 200 µg/kg/day for 2 days, or
thiabendazole, 50 mg/kg/day in two doses (maximum 3 g/day) for 2 days
Lymphedema, hypertrophy of the skin and subcutaneous tissues
Enlargement and deformity of affected parts
Recurrent attacks of acute lymphangitis with chills and fever
Elephantiasis (filariasis)
Tx for filariasis
Diethylcarbamazine X 14 days
often asymptomatic. appearance of symptoms maybe 1 year. The first sign is ofte
Transmitted by Mango fly
painful, localized, subcutaneous, nonpitting edema called
Calabar or fugitive swelling
Worm under conjunctiva, eosinophilia and microfilariae in peripheral blood
Loiasis ( loa loa)
painful, localized, subcutaneous, nonpitting edema
First sign observed in loiasis
Calabar swelling
Tx for loiasis
Diethylcarbamazine
Itchy papular dermatitis localized to one extremity, may become chronic
Transmitted by black fly
After a time, subcutaneous nodules develop that are painful
Onchocerciasis
Tx for onchocerciasis
Ivermectin
Inflict series of bites in a row
“Breakfast, lunch, dinner”
Cimicosis ( bed bug bites)
Tx for trichinosis
Caused by trichenilla spiralis
Albendazole
Tx for cimicosis (bed bug bites)
Permethrin impregnated bednets
Ivermectin 200 ug/kg
aka vagabond’s disease
Pediculosis corporis (pediculosis vestimenti)
is caused by body lice that lay their eggs in the seams of clothing
Treatment for pediculosis
Permethrin
Nit combing
Launder clothing 65C for 30 mins drying
Pruritic papular lesions, excoriations and burrows
Favors finger webs wrists axillar umbilicus lower abdomen genitals buttockss
Dull red nodules may appear during active period in scrotum penis or vulva
Scabies
Axillae, elbow, flexures, wrists and hands and crotch are mostly affected in scabies and is collectively called
Circle of Hebra
Treatment for scabies
Permethrin 5% cream
Benzyl benzoate and 10% precipitated sulfur in white petrolatum
Thoroughly rubbed and washed off 8-10h later
