Polymerase chain reaction in the diagnosis and prognosis of Mediterranean visceral leishmaniasis in immunocompetent children.
OBJECTIVE
To assess the usefulness of a polymerase chain reaction (PCR) assay amplifying the small subunit rRNA coding region of Leishmania species performed on peripheral blood (PB) and bone marrow (BM) aspirates for the diagnosis and follow-up of visceral leishmaniasis (VL) in children living in the Mediterranean basin.


METHODS
A prospective study was conducted on children consecutively hospitalized over a 1-year period at our Infectious Diseases Department in Sicily (Italy) presenting with fever, hepatosplenomegaly, and/or pancytopenia and a positive Leishmania serology (> or =1:40).


RESULTS
Among the 14 patients hospitalized with signs and symptoms suggestive of the disease and a positive serology, we identified 10 cases of Mediterranean VL. PCR performed on PB and BM aspirates was positive in all cases and concordant with microscopy and/or culture performed on BM. Leishmania DNA was cleared from PB a median of 6 days after the start of treatment; during follow-up (median: 9 months; range: 6-12 months) 1 child relapsed. In this case, BM PCR remained positive with rapid reappearance of a positive signal also in PB.


CONCLUSIONS
PB PCR allows a rapid and noninvasive parasitologic diagnosis of Mediterranean VL among immunocompetent children and is at least as sensitive as a diagnosis made on the basis of BM aspirates. The lack of disappearance from BM and the reappearance of positive PCR on PB is predictive of clinical relapse. Qualitative and semiquantitative PCR may be the standard method for monitoring response to therapy in immunocompetent children.
Cascio
Antonio
A
Istituto di Patologia Infettiva e Virologia, Ospedale dei Bambini G. di Cristina, Università di Palermo, Italy.
Calattini
Sara
S
Colomba
Claudia
C
Scalamogna
Chiara
C
Galazzi
Morena
M
Pizzuto
Massimo
M
Camilli
Romina
R
Gramiccia
Marina
M
Titone
Lucina
L
Corbellino
Mario
M
Antinori
Spinello
S
D007898:Leishmaniasis, Visceral / Q000175:diagnosis* / Q000235:genetics; D016133:Polymerase Chain Reaction / Q000706:statistics & numerical data*; D011379:Prognosis; D011446:Prospective Studies