Tropical dermatology: bacterial tropical diseases / Tropical dermatology: bacterial tropical diseases

Bacterial infections are common in tropical parts of the world and can include those species also seen regularly in temperate climates. Many tropical bacterial infections, however, are rarely diagnosed in temperate parts of the world and include bartonellosis, tropical ulcer, tropical pyomyositis, granuloma inguinale, lymphogranuloma venereum, yaws, pinta, melioidosis, and glanders. Some tropical bacterial diseases, eg, plague and anthrax, are associated with high mortality rates and are of potential use in bioterrorism. Some tropical bacterial diseases are closely associated with specific activities such as hunting (ie, tularemia) or eating raw seafood (Vibrio vulnificus infection). The bacterial diseases having the most severe medical impact in the tropics are those caused by members of the Mycobacterium genus. Millions of persons throughout the world suffer from tuberculosis and leprosy; Buruli ulcers are common causes of morbidity in many tropical countries. Because of the increasing frequency of travel to tropical parts of the world for tourism and work as well as the increasing number of immigrants and adoptees from these areas, it is imperative that physicians practicing in temperate climates be able to recognize the signs and symptoms of tropical bacterial diseases, carry out the proper diagnostic tests, and initiate appropriate therapy and prevention. LEARNING OBJECTIVE: At the completion of this learning activity, participants should be familiar with the clinical presentations, epidemiologies, diagnoses, therapies, and preventions of bacterial tropical diseases...

Can a multimedia educational computer-based program on genital herpes teach patients about their disease?

Objective: Education of patients with genital herpes about their disease is time consuming. To evaluate the effectiveness of an educational computer program, we developed a multimedia interactive presentation to teach patients about genital herpes. Such programs can supplement clinician visits for patients with genital herpes, or those at risk for HSV acquisition.Methods: Patients seeking care for genital herpes, or those at risk for HSV acquisition, were asked to participate in the program during routine clinic visits at 5 physician's offices nationwide. A self-administered 7 item herpes knowledge questionnaire was given before and after participation. An additional questionnaire evaluating the satisfaction with the program was also self-administered at completion.Results: 428 patients were enrolled and completed the pre- and post-knowledge questionnaire and 332 patients completed the satisfaction survey. On the pre-test, 20.1% of patients answered all questions correctly, 65.4% answered correctly 4 to 6 questions, and 14.5% 3 or less. On the post-test, 32.9% of patients answered all questions correctly, 61.5% answered correctly 4 to 6 questions, and 5.6% 3 or less (P <.001 for pre- and post-test comparison). A positive change in knowledge between pre- and post-test was seen on 6 of 7 items (P <.001 for all 6). The overall satisfaction with the program was high: the mean rating was 6.2 on a scale 1 (poor) to 7 (excellent).Conclusion: Computer-based education programs about genital herpes may provide a useful adjunct to teaching in physician offices and result in knowledge gain about the disease, at least short-term. Such programs may assist in management of chronic sexually transmitted infections.

Mechanism of action of imiquimod 5% cream in the treatment of anogenital warts.

Objective: The objective of this randomized, double-blind, placebo-controlled trial was to evaluate the mechanism of action of imiquimod cream in the treatment of anogenital warts, and to apply the findings to the results of previously conducted safety and efficacy trials.Methods: Imiquimod (16 patients) or placebo (3 patients) cream was applied 3 times a week for up to 16 weeks; cream remained on the skin overnight for 8 +/- 2 hours. Wart biopsies were taken at prestudy, week 6, and the end of treatment (just prior to clearance or at week 16) and analyzed using PCR for HPV/DNA and RT-PCR for mRNA to identify cytokines, cellular markers, markers of proliferation and differentiation, and viral gene products. Efficacy was assessed based on wart area regression as documented by wart area measurements and photographs.Results: All patients enrolled in the trial had HPV type 6/11. All imiquimod-treated patients experienced a >/=75% clearance in baseline/target wart area. Imiquimod treatment stimulated significant increases in mRNA for IFN-alpha, 2'5' AS and IFN-gamma. Increases in mRNA for CD4, CD8, and TNF-alpha were also observed, suggesting activation of a T-helper type-1 cell mediated response. During the trial one of the vehicle treated patients also experienced spontaneous wart clearance; comparisons of the cytokine levels for this patient were similar to those observed for the imiquimod treated patients.Conclusions: The results of this mechanism of action trial indicate that the stimulation of local cytokines and cellular infiltrates by imiquimod leads to a reduction of HPV types 6 and 11 viral load with subsequent wart regression and normalization of keratinocyte proliferation without evidence of scarring. In two previous randomized vehicle-controlled trials evaluating patients with anogenital warts, the majority of patients had HPV-DNA types 6 or 11 as assessed by in situ hybridization. These results provide additional insight into the mechanism of total clearance for these otherwise healthy patients. The Th1 response demonstrated in this trial also explains the lower total clearance rates demonstrated in HIV-positive and AIDS patients.

Human Papillomavirus Is Associated with Monoclonal Gammopathies of Unknown Significance.

When monoclonal gammopathies arise in persons without evidence of plasma cell malignancy or lymphoproliferative disease, the term 'monoclonal gammopathy of unknown significance' (MGUS) can be used. MGUS is believed to be the preneoplastic phase of lymphoproliferative diseases because many of these patients eventually develop malignant disease, mainly multiple myeloma. We have previously identified human papillomavirus (HPV) in a chronic benign plasma cell tumor of the cervix and in the bone marrow of multiple-myeloma patients. In the following study, we expanded upon our initial observation by analyzing 14 patients with MGUS. Bone marrow biopsies of the patients were analyzed for HPV sequences using polymerase chain reaction (PCR) and in situ hybridization. Normal controls included 26 bone marrow specimens, 24 analyzed by PCR and two by in situ hybridization. A significant association was found to exist between HPV and MGUS (p = 0.001). Among 14 patients with MGUS, HPV sequences have been identified in 10 of the bone marrow biopsies. These results suggest that HPV can reside in the bone marrow of a premalignant lymphoproliferative disease. Copyright 1996 S. Karger AG, Basel