Diagnosis, Treatment and Clinical Features of Cutaneous Leishmaniasis in Saudi Arabia

Cutaneous leishmaniasis (CL) has been one of the most common parasitic diseases in Saudi Arabia. This study exhibits the clinical features, diagnosis, cytokine profile and treatment of CL patients in Al-Taif province. Ninety CL suspects at a tertiary care general hospital were enrolled in one-year study. Patients were interviewed, clinically-examined, and subjected to laboratory tests: skin scraping smear microscopy, OligoC-TesT commercial PCR (Coris BioConcept) and kinetoplast DNA (kDNA) PCR for Leishmania diagnosis. Interferon-gamma (RayBio; Human IFN-γ) and nitric oxide (NO) levels in patients' sera were evaluated before treatment with sodium stibogluconate (pentostam) with 20-day intramuscular drug regimen. Positive rates of microscopy, commercial PCR and kDNA PCR were 74.4%, 95.5% and 100%, respectively. Patients came to hospital mostly in winter (45.0%). CL was frequently exhibited in Saudi patients (78.8%), male gender (70.7%), age < 20 years (50.0%), rural-dwellers (75.5%) and patients with travel history (86.6%). Lesion was mostly single ulcer (93.3%), occurred in the face (67.7%). Upon pentostam treatment, 85.1% of ulcers showed rapid healing signs. Levels of IFN-γ and NO were significantly higher in the healing than the non-healing cases (P < 0.001). The kDNA PCR proved more sensitive than microscopy and OligoC-TesT commercial PCR. Our results open perspectives for IFN-γ use as a biomarker predicting treatment response.

Evaluation of oligochromatography dipstick as a simplified molecular diagnostic tool for the diagnosis of cutaneous leishmaniasis

The demonstration of Leishmania parasite by microscopic examination of samples taken from skin lesions is of low sensitivity and requires expert parasitologists. On the other hand, molecular methods to detect Leishinania parasites are considered specific and sensitive. However, detection of amplicons by the classical methods is complex, expensive and needs equipments and highly trained personnel. This raises the demand for a simplified method of amplification and product detection. To evaluate the diagnostic accuracy of PCR Leishmania Oligo C-test for diagnosis of cutaneous leishmaniasis. The diagnostic accuracy of the Leishniania Oligo C-test was estimated in 30 skin scraping samples from patients presented at El Quorea specialized hospital, Taif, KSA. On the basis of parasitological detection of amastigotes by direct microscopic examination of Geimsa stained smears from skin lesions, patients were classified into confirmed cutaneous Ieishmaniasis [group A] and negative cases [group B]. Twenty patients were proved positive for Leishmania amastigotes by microscopic examination of stained smears. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic efficacy of the Leishmania Oligo C-test were 90%, 90%, 95%, 82%, 90%, respectively. These results indicate that this simple molecular technique may be employed for rapid diagnosis of cutaneous leishmaniasis. The Leishmania Oligo C-test showed high specificity and sensitivity when compared to results obtained by microscopic examination of skin scraping samples. The assay is a promising tool for simplified molecular detection of Leishmania parasites