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shmaniases
Leishmaniases
T h e leish m aniases are a g roup of parasitic d iseases caused by protozoa of th e g enus
Leishmania, transm itted by th e bite of a sand fly. O v er 2 0 species cause d isease in m an.
– Cutaneous leish m aniasis is end em ic in m ore th an 7 0 countries in South and C entral
A m erica, M id d le E ast, C entral A sia, and A frica.
– Mucocutaneous leish m aniasis occurs in L atin A m erica and , m ore rarely, in A frica
(E th iopia, Sud an).
– Visceral leish m aniasis occurs in m ore th an 6 0 countries in E ast and N orth A frica,
South and C entral A sia, South ern E urope, and South and C entral A m erica.
Clinical features
Cutaneous and mucocutaneous leishmaniasis
– Sing le or m ultiple lesions on th e uncov ered parts of th e bod y: an eryth em atous
papule beg ins at th e sand fly bite, enlarg es to a nod ule and extend s in surface and
d epth to form a scabbed ulcer. U lcers are painless, unless th ere is second ary bacterial
or fung al infection. U sually, lesions h eal spontaneously, leav ing a scar, and result in
lifelong protection from d isease.
– L esions m ay also spread to th e m ucosa (m outh , nose, conjunctiv a) g iv ing rise to th e
m ucocutaneous form , w h ich m ay cause sev ere d isfig urem ent.
Visceral leishmaniasis
V isceral leish m aniasis ( kala azar) is a system ic d isease, resulting in pancytopenia,
im m unosuppression, and d eath if left untreated .
– P rolong ed (> 2 w eeks) irreg ular fev er, splenom eg aly, and w eig h t loss are th e m ain
sig ns.
– O th er sig ns includ e: anaem ia, d iarrh oea, epistaxis, lym ph ad enopath y, m od erate
h epatom eg aly.
– B acterial d iarrh oea, pneum onia, and tuberculosis m ay d ev elop d ue to
im m unosuppression.
Post-kala azar dermal leishmaniasis
M acular, nod ular or papular skin rash of unknow n aetiolog y, particularly on th e face,
and typically occurring after apparent cure of v isceral leish m aniasis.
Laboratory
Cutaneous and mucocutaneous leishmaniasis
– P arasitolog ical d iag nosis: id entification of G iem sa- stained parasites in sm ears of
tissue biopsy from th e ed g e of th e ulcer.
– N o useful serolog ical tests.
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Leishmaniases
T h e leish m aniases are a g roup of parasitic d iseases caused by protozoa of th e g enus
Leishmania, transm itted by th e bite of a sand fly. O v er 2 0 species cause d isease in m an.
– Cutaneous leish m aniasis is end em ic in m ore th an 7 0 countries in South and C entral
A m erica, M id d le E ast, C entral A sia, and A frica.
– Mucocutaneous leish m aniasis occurs in L atin A m erica and , m ore rarely, in A frica
(E th iopia, Sud an).
– Visceral leish m aniasis occurs in m ore th an 6 0 countries in E ast and N orth A frica,
South and C entral A sia, South ern E urope, and South and C entral A m erica.
Clinical features
Cutaneous and mucocutaneous leishmaniasis
– Sing le or m ultiple lesions on th e uncov ered parts of th e bod y: an eryth em atous
papule beg ins at th e sand fly bite, enlarg es to a nod ule and extend s in surface and
d epth to form a scabbed ulcer. U lcers are painless, unless th ere is second ary bacterial
or fung al infection. U sually, lesions h eal spontaneously, leav ing a scar, and result in
lifelong protection from d isease.
– L esions m ay also spread to th e m ucosa (m outh , nose, conjunctiv a) g iv ing rise to th e
m ucocutaneous form , w h ich m ay cause sev ere d isfig urem ent.
Visceral leishmaniasis
V isceral leish m aniasis ( kala azar) is a system ic d isease, resulting in pancytopenia,
im m unosuppression, and d eath if left untreated .
– P rolong ed (> 2 w eeks) irreg ular fev er, splenom eg aly, and w eig h t loss are th e m ain
sig ns.
– O th er sig ns includ e: anaem ia, d iarrh oea, epistaxis, lym ph ad enopath y, m od erate
h epatom eg aly.
– B acterial d iarrh oea, pneum onia, and tuberculosis m ay d ev elop d ue to
im m unosuppression.
Post-kala azar dermal leishmaniasis
M acular, nod ular or papular skin rash of unknow n aetiolog y, particularly on th e face,
and typically occurring after apparent cure of v isceral leish m aniasis.
Laboratory
Cutaneous and mucocutaneous leishmaniasis
– P arasitolog ical d iag nosis: id entification of G iem sa- stained parasites in sm ears of
tissue biopsy from th e ed g e of th e ulcer.
– N o useful serolog ical tests.
144
