Visceral and cutaneous leishmaniasis

BACKGROUND: Use of sodium bicarbonate (NaHCO3) may result in intracellular acidosis due to the generation of CO2. Carbicarb, has been reported to be superior to sodium bicarbonate (NaHCO3) because of lesser generation of CO2. The present study was designed to investigate whether Carbicarb or NaHCO3 is superior to normal saline in the treatment of hypoxic lactic acidosis. METHODS: Hypoxia was induced by ventilation with 8% O(2) in 30 piglets with fixed ventilation. When the pH fell to < 7.2, hypoxia was reversed by placing the animals in 21% O2 (experiment 1) or 100% O(2) (experiment 2) and either saline, Carbicarb or NaHCO3 were given. Data were collected for 120 minutes after therapy. RESULTS: In both experiment 1 (severe acidosis, pH < or = 7.1) and 2 (moderate acidosis, pH < or = 7.2) use of Carbicarb and NaHCO3 increased the arterial carbon dioxide tension (pCO2) significantly (p < 0.05). With moderate acidosis: 1) use of alkalinizing agents compared to saline resulted in an initial improvement in arterial pH at 1 minute, but thereafter, the differences were not statistically significant; and 2) there were no differences in hemodynamic variables and plasma lactic acid concentration between the three groups. CONCLUSIONS: The data demonstrate that 1) both Carbicarb and NaHCO3 significantly increase arterial pCO2; and 2) use of either alkalinizing agent in moderate acidosis does not alter the course of acidosis.     

Visceral and cutaneous leishmaniasis comparative ultrastructure of host-parasite interactions

The comparative ultrastructure of host-parasite interactions is described for the first time in patients with visceral (VL) and cutaneous (CL) leishmaniasis. In patients with VL, the parasite invades the bone marrow (BM) macrophages (Mcs) and neutrophils, while in patients with CL, the parasite invades the dermal fibroblasts in addition to Mcs. The skin Mcs seem to have more lethal effects on the parasite than the BM Mcs; this is possibly due to the presence of numerous melanosomes with acid phosphatase activity in the Mcs digestive vacuole. In patients with high level of VL parasitaemia, the parasite may induce the BM reticulocytes to phagocytose both the parasite and mature erythrocytes, i.e. lost recognition. In patients with low level of VLparasitaemia, the parasite may induce the BM Mcs to be haemophagocytic, i.e. temporarily mimick malignant histiocytosis until the course of treatment. In early stages of CL infection, the cellular infiltrate consists of the monocyte-macrophage system, plasma cells, lymphocytes and fibroblasts; while in the late stages, two types of epithelioid cells (ECs) are added to the infiltrate and are involved in the formation of tuberculous granulomas. Type I ECs thought to produce a granuloma factor, while type II ECs possibly precedes healing by fibrosis. However, the severity of host-parasite interactions seems to depend mainly on species of the parasite, the degree of parasitaemia, the type of infected tissue(s), and the variation of host tissue reaction against the parasite from one patient to another.     

Cryosurgery in cutaneous leishmaniasis

Thirty patients with cutaneous leishmaniasis were treated with cryotherapy using a CO2 cryomachine and all were cured without noticeable scarring within 4-5 weeks, with no relapse. Histopathological examination showed that cryotherapy eradicated all parasites in less than 1 hour. Leishmania tropica, L. ethiopica and L. brasiliensis are all markedly thermosensitive and thus cryotherapy seems parasiticidal to all types. Adequate cryotreatment of cutaneous leishmaniasis will preclude the development of mucocutaneous extension, and its use in mucocutaneous disease is also recommended.     

Visceral leishmaniasis in District Dir, NWFP

Visceral leishmaniasis is endemic in District Dir, NWFP. We evaluated 10 patients with visceral leishmaniasis at DHQ Hospital Timergara District Dir, N.W.F.P. All patients were in the age range 2 to 10 years. The predominant clinical features in these were chronic fever (10), splenomegaly (10), hepatomegaly (10), weight loss (10) and abdominal distention (5). Lymphadenopathy was absent. Common laboratory abnormalities included anaemia (10), leucopenia (7), thrombocytopenia (10) and hypergammaglobulinaemia (10). Formal Gel test was positive in all patients (100%) and all had positive bone marrow smears for Leishmania Donovani (L.D.) bodies (10). The response to stibogluconate (Glucantime Sodium) therapy was good with a 100 percent cure rate.     

The epidemiology of cutaneous leishmaniasis in Kuwait

Studies in Kuwait have suggested that sandflies feed on man and domestic animals, but not on rodents in different habitats. Of 1129 feral and wild rodents, none showed evidence of leishmanial infection nor did their incidental lesions resemble those produced by inoculating a human strain. Five out of 30 patients with lesions of cutaneous leishmaniasis claimed they had never been outside the country, but the validity of these claims is questioned. Cutaneous leishmaniasis in Kuwait is essentially an imported disease, with no substantial evidence that it is yet endemic.     

Multiple cutaneous leishmaniasis after a stay in Central America

Leishmaniasis is a protozoal disease affecting at least 12 millions persons, with 400,000 new cases per year. It is transmitted by a small insect, the phlebotomine sand fly. Clinical syndromes include visceral leishmaniasis and various cutaneous affections. We describe here the case of a patient affected by a multiple lesions New World cutaneous leishmaniasis, after staying in Costa Rica for tourism; we discuss the differential diagnosis and make a short summary of the principles of treatment.     

Short report epidemiologic studies on cutaneous leishmaniasis in eastern Panama

In this study, we investigate the innervation to the feline ophthalmic artery by the horseradish peroxidase (HRP) tracing method. Five adult cats with body weights ranging between 2.0 and 3.0 kg were used. Under microscopic dissection, the ophthalmic artery was identified and isolated. A gelfoam (Upjohn Co.), 1 x 3 mm in size, containing 0.1 ml of HRP was applied to the prepared artery segment for 2 h. The cat was sacrificed 3 days later. The trigeminal, stellate, superior cervical, middle cervical and nodal ganglia, and oculomotor, trochlear and abducens nuclei were removed, sectioned and stained for HRP-positive cells. HRP-labeled neurons were found in the ipsilateral trigeminal (TRG) and superior cervical ganglia (SCG). The middle cervical, stellate, Edinger-Westphal, trochlear and abducens nuclei were all deemed negative for HRP-labeled cells. In the TRG, HRP-labeled neurons ranged from 21 to 250 (mean +/- SE = 93.8 +/- 42.5/ganglion). The labeled neurons were distributed primarily in the ophthalmic branch. In the SCG, the HRP-labeled neurons were distributed evenly in the ganglion, ranging from 6 to 180 (mean +/- SE = 91.6 +/- 31.5/ganglion). Two additional cats having received a sham operation revealed a negative finding. The feline ophthalmic artery is innervated by the ipsilateral TRG and SCG. Such innervation may play a role in regulating blood flow to the optic nerve.     

Changing patterns of cutaneous leishmaniasis in Israel and neighbouring territories

The most frequent form of cutaneous leishmaniasis (CL) in Israel and the neighbouring territories is due to Leishmania major, which is endemic mainly in the Jordan Valley and in the Rift Valley. CL due to L. tropica is much less common, and in the past only sporadic cases have been reported. In this study we present data obtained during the years 1988-1992 regarding CL in the area. Our clinic has diagnosed a total of 371 leishmaniasis cases, most of whom acquired the infection in the Jordan Valley, mainly during June and July. About one-third of the patients had single lesions, and one-third more than 5 lesions. We also describe an outbreak of leishmaniasis in Kfar Adumim, a village 15 km east of Jerusalem, where leishmaniasis was previously unknown. Parasites were characterized by the polymerase chain reaction and by immunostaining, and found to be both L. tropica and L. major. The localization of the homes of the affected people on a slope where hyraxes were abundant suggests that these animals might have been involved in the transmission of L. tropica in this area.     

A new intralesional therapy of cutaneous leishmaniasis with hypertonic sodium chloride solution

One hundred and fifty-eight lesions of acute cutaneous leishmaniasis in 70 patients were treated with hypertonic sodium chloride solution "HSCS" (88 lesions) or sodium stibogluconate (50 lesions); 20 lesions were left untreated as controls. The injections were given at 7-10 day intervals, and patients were followed-up for 42 days. "HSCS" was shown to be a very effective local therapy (96.05% cure rate) and was as effective as local sodium stibogluconate (96.42% cure rate). With both types of therapy, most lesions needed only one injection. Mild improvement was noticed 7-10 days after the first injection, and the cure was complete within 2-6 weeks (mean 4 weeks) of follow-up. None of the control lesions showed a cure within the six weeks follow-up. The mechanisms of action of both "HSCS" and sodium stibogluconate probably involve interference with the osmotic pressure of the cell cytoplasm of the parasites and lesional tissues. Scarring was either absent or minimal following healing of the treated lesions with both types of treatment. Post-inflammatory hyperpigmentation was observed in all patients. We strongly recommend intralesional "HSCS" as a cheap, safe, and effective local method for treating cutaneous leishmaniasis.     

Some aspects of cutaneous leishmaniasis in Riyadh. Saudi Arabia

One hundred and sixty nine out of 310 outpatients of Riyadh's hospitals and 104 out of 209 inhabitants from El Kharj showed Leishmania bodies in smears obtained by puncture of indurated edge of sores. Collection of sand flies yielded P. papatasi, Paraphlebotomus caucasicus and S. squamipleuris. The results were discussed.     

Visceral leishmaniasis in the hoary zorro Dusicyon vetulus: a case of mistaken identity

The historical identification of the Brazilian 'north-eastern' zorro as Dusicyon vetulus is questioned in relation to its incrimination as a reservoir of Leishmania chagasi, the agent of American visceral leishmaniasis. Comparative cranial and dental morphology showed that specimens of this north-eastern species more closely resemble the crab-eating zorro Cerdocyon thous, conforming with the documented geographical ranges of the respective species. We conclude that the single 'wild' canid host of L. chagasi in the neotropics in C. thous.