Ibrahim M. Mosleh

Efficacy of a weekly cryotherapy regimen to treat Leishmania major cutaneous leishmaniasis

BACKGROUND Antileishmanial chemotherapy can have adverse effects and may fail to cure patients with cutaneous leishmaniasis (CL). OBJECTIVE To evaluate the efficacy of a weekly cryotherapy regimen in patients with confirmed Leishmania major infection. METHODS One hundred twenty Jordanian patients with 375 lesions were treated with cryotherapy performed once weekly in 1 to 7 sessions. This regimen was adopted since living parasites were recovered, in several CL patients, even after 3 cryosessions. Scarring was assessed in 78 patients 3 years after treatment. RESULTS Approximately 84% of the lesions were cured after 1 to 4 sessions. The remaining lesions (16.3%) were cured after an additional 1 to 3 session(s). Cryotherapy caused mild adverse side effects and most of the patients were cured with negligible scarring. Statistically, the lesion size and location significantly affected the clinical response to cryotherapy. LIMITATIONS A fraction of patients was followed up 3 years after healing. CONCLUSION Cryotherapy with weekly intervals for 1 to 4 sessions is effective to treat L major CL, especially for smaller lesions. Extra sessions may be necessary to cure larger lesions. The cosmetic results are very good and no relapses were registered.

Synthesis of novel hybrid molecules from precursors with known antiparasitic activity.

Three novel new compounds derived from antiparasitic precursors have been synthesized and tested for their antiamoebic and antigiardial activities. The condensation of 2-(2-methyl-5-1H-nitroimidazolyl)ethylamine (6) with 5-nitro-2-furylacrylic acid (7) gave 3-(5-nitrofuran-2-yl)-N-[2-(5-nitroimidazol-1-yl)ethyl]acrylamide (8). Condensation of 7 with 7-chloro-4-(piperazin-1-yl)quinoline (9) afforded 1-[4-(7-chloroquinolin-4-yl)piperazin-1-yl)-3-(5-nitrofuran-2-yl)propenone as a mixture of two isomers; 10-a (the E-isomer) and 10-b (the Z-isomer). In addition, the reaction of 9 with 1-(2-bromoethyl)-2-methyl-5-nitroimidazole (11) in the presence of K2CO3 and NaI yielded 7-chloro-4-(4-[2-(5-nitroimidazol-1-yl)ethyl]-piprazin-1-yl)quinoline (12). On the basis of preliminary screening data for these new compounds, compound 12 exhibited potent lethal activities against Entamoeba histolytica and Giardia intestinalis; its IC50 ( about 1 µM) was lower, at least by a factor of five, compared to the standard drug, metronidazole. In addition, the IC50 of compound 12 against the tested parasites is 600 times below that against Hep-2 and Vero cells. Compounds 8 and 10-a also exhibited potent or moderate antiamoebic and antigiardial activities with IC50 values of about 5.5 µM, and 140 µM, respectively, against the tested parasites. These two hybrid molecules, 8, 10-a, were also non-cytotoxic at the lethal concentrations against the parasites.

Cutaneous leishmaniasis in the Jordanian side of the Jordan Valley: severe under-reporting and consequences on public health management

Objective  To test if cutaneous leishmaniasis (CL) is under‐reported in the Jordanian Mid Jordan Valley, with resultant serious consequences for drug supply.

Serodiagnosis of cutaneous leishmaniasis in Jordan using indirect fluorescent antibody test and the enzyme-linked immunosorbent assay

The usefulness of IFAT and ELISA, in the detection of antibodies to cutaneous leishmaniasis (CL) in Jordanian cases was studied. Serum samples were collected from three groups of confirmed or putative CL patients (n = 100), 132 healthy blood donors, 10 patients with pulmonary tuberculosis (TB), and 16 patients with typhoid fever (TF). Antigens for both tests were prepared from promastigotes of a Leishmania major isolate. At a serum dilution of respectively 1:16 and 1:100 both IFAT and ELISA had a sensitivity of 81%, whereas in the healthy control group their specificities were 95 and 96%. Maximal titers in the 37 parasitologically-proven cases were 1:128 in IFAT and 1:800 in ELISA. Antibodies were detected in about 50% of the 42 cases that had negative parasitological tests but had typical lesions with IFAT-titers up to 1:64 and ELISA titers up to 1:400. However, antibodies were detected in 19% of the 21 clinically-suspected cases of CL with maximal titers of 1:32 in IFAT and 1:200 in ELISA. A variation in antibody level was detected in the treated and the non-treated patients who were followed up for few months after diagnosis. One serum specimen taken from a patient with TB and two sera taken from patients with TF cross-reacted with Leishmania antigens in both IFAT and ELISA. This false positivity could be eliminated by absorption of these sera with their homologous antigens. There was no significant relationship between antibody level and duration of infection with CL. On the other hand, a significant relationship between antibody level and number of CL lesions was found. Although both tests would be useful for detection of circulating antibodies in cases suspected of having CL, especially in those having several lesions, IFAT is recommended for use in Jordan for its simplicity and rapidity.

New Synthesis and Antiparasitic Activity of Model 5-Aryl-1- methyl-4-nitroimidazoles

A number of 5-aryl-1-methyl-4-nitroimidazoles 5a-f have been synthesized in good yields by the Suzuki coupling reaction between 5-chloro-1-methyl-4-nitroimidazole (3) and arylboronic acids 4a-f, aided by dichlorobis-(triphenylphosphine)palladium(II), K2CO3, and tetrabutylammonium bromide in water at 70-80 °C. Compounds 5a-f were characterized by elemental analysis, NMR and MS spectral data. On the basis of in vitro screening data, 5-(3-chlorophenyl)-1-methyl-4-nitro-1H-imidazole (5f) exhibited potent lethal activity against Entamoeba histolytica and Giardia intestinalis with IC50 = 1.47 µM/mL, a value lower by a factor of two than that of the standard drug, metronidazole. The boosted activity of 5f was not accompanied by any increased cytotoxicity. The rest of the series also exhibited potent antiparasitic activity with IC50 values in the 1.72-4.43 µM/mL range. The cytotoxicity of the derivatives 5c and 5e was increased compared to the precursor compound, metronidazole, although they remain non-cytotoxic at concentrations much higher than the antiparasitic concentration of the two derivatives.

Chemical constituents of Osyris alba and their antiparasitic activities

Phytochemical investigation of Osyris alba L. (Santalaceae) of Jordanian origin resulted in the isolation and identification of one new pyrrolizidine alkaloid, osyrisine (1), together with 16 other known compounds. The structures of all compounds were established on the basis of spectroscopic analysis. Osyrisine, catechin, and catechin-3-O-α-l-rhamnopyranoside exhibited a significant level of antiparasitic activity against two parasites, Entamoeba histolytica and Giardia intestinalis.

Two recent but temporally distinct outbreaks of cutaneous leishmaniasis among foreign workers in the Dead-Sea area of Jordan

Abstract Two temporally distinct outbreaks of human cutaneous leishmaniasis (CL), as well as scattered cases of the disease, have recently been observed close to the Dead Sea, in Jordan. Each of the two outbreaks, which occurred in 2004/2005 and 2007/2008, involved a group of foreign workers who were deployed within otherwise uninhabited locations. During each outbreak, about 20% of the workers were found infected with the causative parasite. In the earlier outbreak, 61 workers were found to have skin lesions like those of CL and all but three were confirmed by culture and/or the examination of smears (40 cases) or, in the case of 18 (86%) of the 21 suspected cases found smear- and culture-negative, by PCR. In the second outbreak, the cases were only identified from their clinical manifestations and their response to antileishmanial treatment (cryotherapy). Leishmania major was identified as the cause of the 2004/2005 outbreak and some sporadic cases that occurred, in 2004, along the shores of the Dead Sea. The burrows of potential reservoir hosts were found close to the outbreak locations, frequently under the chenopod Seidlitzia rosmarinus. The two outbreaks emphasise the continuing problem posed by the CL focus in the Mid Jordan Valley and its impact on humans who move into the area. Curiously, an investigation on the socio–economic conditions of the workers during the outbreaks identified a group of 48 workers who were living in air-conditioned rooms during the 2007/2008 outbreak, among whom no CL cases were found. In contrast, 26 of a neighbouring group of 124 workers, who were all living in non-air-conditioned rooms, developed CL lesions. The role of air conditioning, and of other factors and measures, in the prevention of the transmission of the causative parasites of CL merits further investigation and the attention of the local health authorities.

The Jordanian Mid Jordan Valley is a classic focus of Leishmania major as revealed by RFLP of 56 isolates and 173 ITS-1-PCR-positive clinical samples

The identity of the causative species of cutaneous leishmaniasis (CL) in the endemic Jordanian Mid Jordan Valley (JMidJV) was investigated using the polymerase chain reaction (PCR) amplifying the ribosomal internal transcribed spacer 1 (ITS-1) followed by the restriction fragment length polymorphism (RFLP). The geographical distribution of CL and the usefulness of ITS1 PCR in diagnosis of suspected CL in the study area were also addressed. Over the period from 2004 to 2009, 56 clinical isolates of Leishmania promastigotes and 185 lesion scrapings spotted on filter papers were obtained from suspected CL patients living in the JMidJV, which is divided into northern and southern districts. The majority (67.1%) of patients occurred in the populated eastern part of the southern district. Of the 185 suspected CL patients, 173 (93.5%) were confirmed positive using PCR. Leishmanial DNA was detected in 27 (90%) of 30 patients having clinically atypical lesions of CL and in 60 (92%) of 65 smear- and culture-negative cases having typical lesions of CL. The parasites in all of the 56 isolates and the 173 PCR-positive scrapings were classified as Leishmania major. In conclusion, PCR is useful in diagnosis of CL especially when smear and culture are negative. It is also recommended as a differential diagnostic tool of atypical lesions when CL is endemic. The identification of L. major as the causative species in such a considerable number of CL cases, representative of all mini foci of CL in the study area, shows that the JMidJV is a classic focus of L. major.

Leishmania major cutaneous leishmaniasis outbreak in the Jordanian side of the Northern Jordan Valley

Abstract Cutaneous leishmaniasis (CL) is endemic in many foci of Jordan and the Jordanian Mid Jordan Valley (JMJV) is the most affected and the incidence is quite high. The situation in the northern part of the Jordanian side of the Jordan Valley (NJJV) was different; before 2008, CL has rarely been reported from this area. From April 2008 to May 2009, passive detection followed by active detection was used to trace cases of CL from the NJJV. DNA was extracted from seven clinical isolates of Leishmania promastigotes and lesion scrapings spotted on filter papers obtained from 51 suspected CL patients living in the NJJV. The identity of the causative species of CL in the NJJV was investigated using ITS1-PCR followed by RFLP. In 2008/2009, 183 cases were clinically diagnosed of having CL in the NJJV. The parasites in five of the isolates and in 48 PCR-positive scrapings were classified as Leishmania major. In two isolates and in one PCR-positive scraping Leishmania tropica was identified. Investigations on the origin of CL cases revealed that the L. tropica cases were residents of two towns outside the NJJV. Herein, we report the clinical features, parasitological diagnosis, etiology, and the geographical distribution of CL cases from NJJV with the aim of documenting, for the first time, an outbreak in this area.