Molecular characterization of Giardia duodenalis in children from the Cufada Lagoon Natural Park, Guinea-Bissau.

Molecular characterization of Giardia duodenalis in African countries is relatively scarce. The global understanding of Giardia epidemiology is reinforced when more data are available from highly endemic countries. In the present study, 50 fecal samples collected from children from Guinea-Bissau were screened for Giardia infection. Amplification of the Giardia ssu-rRNA fragment was achieved for 28 samples (28/50, 56.0 %) of which 23 (23/50, 46.0 %) positive samples for Giardia were detected through microscopy. Eighteen samples previous amplified for the ssu-rRNA locus were amplified for the bg gene fragment. Sequence analysis was performed in 26 and 17 samples for the ssu-rRNA and bg gene fragment, respectively. Our results revealed a predominance of assemblage B (22/26, 84.6 %), sequences with high genetic polymorphism among isolates belonging to this assemblage, making impossible the subassemblage determination. Assemblage A was identified in three isolates (3/26, 11.5 %), and our results strongly suggest that two isolates belong to subassemblage A2. This study provides information about G. duodenalis genotypes in a rural area of Guinea-Bissau and may contribute for a better understanding of giardiasis epidemiology in this country.

Lawsonella clevelandensis as the causative agent of a breast abscess.

Lawsonella clevelandensis is a Gram-stain-positive, partially acid-fast, anaerobic, being considered a new species within a new genus in the suborder Corynebacterineae. There are only a few cases reported worldwide. This is a fastidious microorganism, difficult to identify by conventional methods, leading to inappropriate treatments. The authors report a case of a 29-year-old woman with a 3-week evolution of a breast nodule. There was a family history of breast carcinoma. Samples were collected for histological and microbiological examination. Gram staining revealed Gram-positive filamentous bacilli, acid-fast-positive. The cultural examination revealed a Lawsonella clevelandensis that was confirmed by molecular methods. At the last follow up, the evolution was favorable; the abscess was resolved, with no evidence of recurrence. To our knowledge the present case was the first reported in Europe.

Treatment of cryptococcosis with liposomal amphotericin B (AmBisome) in 23 patients with AIDS.

OBJECTIVE: To determine the safety and efficacy of liposomal amphotericin B (AmBisome) in the primary treatment of AIDS-associated cryptococcosis. DESIGN: A Phase II, multicentre, European, non-comparative, open study to assess the use of AmBisome in 23 patients (26 enrolments) with cryptococcosis. Dose requirements, mycological response and toxicity were documented. SETTING: Hospital-based HIV units. PATIENTS: Twenty-three HIV-1-seropositive patients. RESULTS: Drug toxicity, assessed in 25 enrolments, was well-tolerated with little renal, hepatic or haematological toxicity. Eighteen out of 23 (78%) enrolments responded clinically. Nineteen enrolments had cryptococcal meningitis: sterilization of spinal fluid was achieved in 12 out of the 18 (67%) who were mycologically evaluable. Fourteen out of the 19 (74%) responded clinically. CONCLUSION: AmBisome is well-tolerated and may be an effective formulation in the treatment of cryptococcosis.

Epidemiology and clinical features of imported dengue fever in Europe: sentinel surveillance data from TropNetEurop.

Travelers have the potential both to acquire and to spread dengue virus infection. The incidence of dengue fever (DF) among European travelers certainly is underestimated, because few centers use standardized diagnostic procedures for febrile patients. In addition, DF is currently not reported in most European public health systems. Surveillance has commenced within the framework of a European Network on Imported Infectious Disease Surveillance (TropNetEurop) to gain information on the quantity and severity of cases of dengue imported into Europe. Descriptions of 294 patients with DF were analyzed for epidemiological information and clinical features. By far the most infections were imported from Asia, which suggests a high risk of DF for travelers to that region. Dengue hemorrhagic fever occurred in 7 patients (2.4%) all of whom recovered. Data reported by member sites of the TropNetEurop can contribute to understanding the epidemiology and clinical characteristics of imported DF.

Epidemiology and clinical features of vivax malaria imported to Europe: sentinel surveillance data from TropNetEurop.

BACKGROUND: Plasmodium vivax is the second most common species among malaria patients diagnosed in Europe, but epidemiological and clinical data on imported P. vivax malaria are limited. The TropNetEurop surveillance network has monitored the importation of vivax malaria into Europe since 1999. OBJECTIVES: To present epidemiological and clinical data on imported P. vivax malaria collected at European level. MATERIAL AND METHODS: Data of primary cases of P. vivax malaria reported between January 1999 and September 2003 were analysed, focusing on disease frequency, patient characteristics, place of infection, course of disease, treatment and differences between network-member countries. RESULTS: Within the surveillance period 4,801 cases of imported malaria were reported. 618 (12.9%) were attributed to P. vivax. European travellers and immigrants were the largest patient groups, but their proportion varied among the reporting countries. The main regions of infection in descending order were the Indian subcontinent, Indonesia, South America and Western and Eastern Africa, as a group accounting for more than 60% of the cases. Regular use of malaria chemoprophylaxis was reported by 118 patients. With 86 (inter-quartile range 41-158) versus 31 days (inter-quartile range 4-133) the median symptom onset was significantly delayed in patients with chemoprophylaxis (p < 0.0001). Common complaints were fever, headache, fatigue, and musculo-skeletal symptoms. All patients survived and severe clinical complications were rare. Hospitalization was provided for 60% and primaquine treatment administered to 83.8% of the patients, but frequencies varied strongly among reporting countries. CONCLUSIONS: TropNetEurop data can contribute to the harmonization of European treatment policies.

Successful treatment of experimental murine Trypanosoma brucei infection with topical melarsoprol gel.

Melarsoprol gel applied topically (0.1 mL for at least 2 d) can cure late-stage Trypanosoma brucei brucei and T. b. rhodesiense infections in mice. The best regimen was 3 applications at approximately 0, 6, and 24 h. The melarsoprol gel retained its activity at room temperature for at least 63 d. There was only minimal skin irritation and no sign of toxicity.

The importance of 2,3-dimercaptopropinol (British anti-lewisite, BAL) in the trypanocidal activity of topical melarsoprol.

Both melarsomine dichlorhydrate (mel Cy, Cymelarsan) and melarsen oxide can be dissolved in dimethylsulfoxide and converted into a gel by the addition of hydroxypropylcellulose. When Trypanosoma brucei brucei-infected mice are treated topically with these gels the circulating trypanosomes are rapidly cleared from the circulation but the infections relapse soon after the last application. However, when these two compounds are allowed to react with 2,3-dimercaptopropinol (British anti-lewisite, BAL) and form "melarsoprol" their efficacy, especially in the case of mel Cy, is restored to that of commercial melarsoprol (Arsobal) and trypanosomes in the central nervous system (CNS) can be eliminated. This would indicate that the dimercaptopropinol portion of the molecule does not act solely as an "antidote" to arsenic toxicity, but also plays an important role in the absorption of melarsoprol through the skin and/or blood-brain barrier into the CNS and/or into the trypanosome.

Intestinal parasites in dogs and cats from the district of Évora, Portugal.

Intestinal parasites, both helminths and protozoa, are commonly found in domestic animals, and the possible transmission of enteric parasites from dogs and cats to humans may constitute a global potential health risk worldwide. In the present study, we analysed 148 stool samples from dogs (n=126) and cats (n=22) collected from animal shelters and veterinary clinics, in the district of Évora, Portugal. Microscopic examination confirmed that Giardia was the most frequent parasite in the studied population (34/148; 23%). Other parasites such as Ancylostoma sp., Isospora spp., Toxocara, Trichuris spp., Toxascaris and Toxoplasma were also found. Furthermore, molecular characterization of Giardia duodenalis analysis targeting the small subunit ribosomal RNA (ssu-rRNA) was performed revealing the presence of host-specific (C and D) and zoonotic assemblages (A and B). This work points out to the importance of protozoan parasites in companion animals, and reanalyses the need for parasite prophylaxis.

Therapy of human African trypanosomiasis: current situation.

This paper is a review of the current situation of the treatment of human African trypanosomiasis. The existing approved drugs are old, toxic and/or expensive. Therapeutic failures are common. Several factors may contribute to the problems of chemotherapy, including differences in the epidemiology of the disease, difficulties in the diagnosis and staging of the infection, availability, distribution and pharmacologic properties of drugs, standardization of treatment regimens, response to therapy, follow-up period, and relapses and clinical trials. The new therapeutic approaches include the development and approval of new drugs, the use of new therapeutic regimens, the study of drug combinations, and the development of new formulations.

Topical chemotherapy for experimental murine African CNS-trypanosomiasis: the successful use of the arsenical, melarsoprol, combined with the 5-nitroimidazoles, fexinidazole or MK-436.

The 5-nitroimidazoles, MK-436 and fexinidazole dissolved in dimethylsulphoxide can be converted by the addition of hydroxypropylcellulose into gels which facilitates the ease and accuracy of administration. When these gels are used in combination with melarsoprol gel they are capable of curing experimental murine CNS-trypanosomiasis with a one-day treatment. The use of melarsoprol/MK-436 was more efficient than melarsoprol/fexinidazole gels. Thus while a single treatment with 0.1 ml 3.6% melarsoprol gel with 0.1 ml (14.3 mumol) fexinidazole gel cured the infected mice, the same dose of melarsoprol gel with 0.1 ml (4.0 mumol) of MK-436 gel was equally effective. It was also possible to prepare a combined melarsoprol/MK-436 gel which cured experimental CNS-trypanosomiasis with a single treatment. Topical treatment with this melarsoprol/MK-436 gel mixture also resolved clinically the hind leg paralysis which is associated with post-treatment reactive encephalopathy caused by non-curative treatment of CNS-trypanosomiasis.

Activity of phenothiazines against antibiotic-resistant Mycobacterium tuberculosis: a review supporting further studies that may elucidate the potential use of thioridazine as anti-tuberculosis therapy.

The in vitro and in vivo anti-mycobacterial activities of a number of phenothiazine compounds are reviewed. These compounds, normally employed for the management of psychosis, inhibit the growth in vitro of Mycobacterium tuberculosis at concentrations that are significantly greater than those that can safely be achieved in a patient harbouring these infections. Nevertheless, one of these phenothiazines, chlorpromazine, is concentrated by human macrophages to 10-100 times its concentration in plasma, and has activity against mycobacteria that have been phagocytosed by these cells. Phenothiazines have significant in vitro activity against susceptible, polydrug- and multidrug-resistant strains of M. tuberculosis, as well as enhancing the activity of some agents employed for first-line treatment. Because thioridazine, the very mild anti-psychotic agent whose most common side effect is drowsiness, has equal anti-tuberculosis properties in vitro to chlorpromazine, we recommend that thioridazine be studied as an adjuvant to the four- or five-drug regimens employed for the management of a freshly diagnosed tuberculosis infection of unknown antibiotic susceptibility, at least during the period required for the assessment of antibiotic susceptibility. Because it also enhances the activity of rifampicin and streptomycin, antibiotics that frequently have adverse effects, additional studies evaluating the use of thioridazine as an adjuvant may eventually allow a reduction in the dosages of these antibiotics and result in a decreased frequency of adverse effects. It is important to note that whereas the management of patients with thioridazine for periods in excess of many months will result in the appearance of some undesirable side effects, its use for a limited period of 2-3 months should not produce side effects that are more severe than simple drowsiness. Nevertheless, further in vitro and in vivo studies are essential before thioridazine may be recommended for the management of select cases of pulmonary tuberculosis.