Leishmania

Question 1

etio

Answer 1

Etiology.Many species of obligate intracellular protozoa Leishmania;predominant species are:
■ New World: Leishmania mexicana complex, Viannia subgenus.
■ Old World:L.tropica,L.major,and L.aethiopica.

Question 2

Vector

Answer 2

Vector.Sandfies.OldWorld:Phlebotomus.NewWorld:Lutzomyia

Question 3

Pathogenesis

Answer 3

In ection o macrophages in skin, naso-oropharyngeal mucosa, and the reticuloen-
dothelialsystem(viscera).Diversityo clinicalsyndromesresulting romaparticularparasite,vector, and host species.

Question 4

characterized bydevelopmento singleormultiplecutane- ouspapulesatthesiteo asand ybite,o en evolving into nodules and ulcers, which heal spontaneously with a depressed scar.

Answer 4

Cutaneous leishmaniasis

Question 5

stages of parasite

Answer 5

Stageso parasite:Promastigote: Flagellated form found in sandflies and culture; amastigote: non agellated tissue orm

Question 6

transmission

Answer 6

Vector-borne by bite o in ected

emalephlebotominesand ies,whichbecome in ected by taking blood meal rom in ected mammalian host

Question 7

incubation period

Answer 7

Inversely proportional to size o inoculum:Shorterinvisitorstoendemicarea. OWCL: L. tropica major, 1 to 4 weeks; L. tropica, 2 to 8 months; acute CL: 2 to 8 weeks or more

Question 8

symptoms

Answer 8

Noduloulcerativelesionsusually asymptomatic. With secondary bacterial in ec- tion, may become painful

Question 9

NEW WORLD CUTANEOUS LEISH . skin manif

Answer 9

Small erythema- tous papule develops at sand y bite site, evolv- ing into ulcerated nodule
elarges to 3 to 12 cm with raised border. Nonulcerating nodules may become verrucous. Lymphangitis, regional lymphadenopathy

Ear lesions may persist or years, destroying cartilage (chiclero ulcers)

Question 10

Mucocutaneous leish. skin manif

Answer 10

Characterized by naso-oropharyngeal mucosal involvement

Edemaandin ammatorychangesleadto epistaxis and coryzal symptoms. In time, the nasal septum, oor o the mouth, and tonsil- lar areas are destroyed (Fig. 29-3). Results in marked disf gurement (re erred to as espundia inSouthAmerica).Deathmaybecausedby superimposed bacterial in ection, pharyngeal obstruction, or malnutrition.

Question 11

old world cut leish. manif

Answer 11

Begins as small erythematous papule, which may appear immediately a er sand y bite but usually 2 to 4 weeks later. Papule slowly enlarges to 2 cm over a period o several weeks and assumes a dusky violaceous hue (Figs. 29-4 and 29-5). Eventually, lesion becomes crusted

in center with a shallow ulcer and raised indu- rated border = volcano sign. In some cases, the center o the nodule becomes hyperkera- totic, ormingacutaneoushorn

Question 12

Complication
of L.tropica infection.Dusky-redplaqueswith active,spreadingbordersandhealingcenters, giving rise to gyrate and annular lesions. Most commonlya ectsthe ace;cancausetissue destruction and severe deformity.

Answer 12

LEISHMANIASIS RECIDIVANS(LR)

Question 13

SequeltoVLthathasresolvedsponta- neously or during/a er adequate treatment. Lesionsappear≥1yeara ercourseo therapy
with macular, papular, nodular lesions, and hypopigmentedmacules/plaqueson ace (Fig.29-6),trunk,andextremities

Answer 13

post kala azardermal leishmaniasis

Question 14

Dx

Answer 14

Clinical suspicion, confirmed by demonstrating:
■ Intracellular non agellated amastigote in a biopsyo skin,mucosa,liver,lymphnodesor
aspirate o spleen, bone marrow, and lymph
node.
■ Flagellated promastigote in culture o tissues
(requiresupto21days)

Question 15

Tx

Answer 15

sodium stibogluconate

alt : amphotericin B, miltefosine,paromomycin,and pentamidine