Dermatobia Hominis Infestation Misdiagnosed as Abscesses in a Traveler to Spain.

Dear Editor, A 29-year-old woman presented with abscesses on her buttock and leg attributed to flea bites inflicted 5 days earlier on return to Spain after 2 months in Guinea-Bissau. Ciprofloxacin was ineffective after 7 days, and she was referred for dermatologic evaluation. Examination revealed 4 round, indurated, erythematous-violet furunculoid lesions with a 1.5-2 mm central orifice draining serous material. She reported seeing larvae exiting a lesion, and we extracted several more (Figure 1). Parasitology identified Dermatobia (D.) hominis (Figure 2). Biopsy revealed intense dermal eosinophilic inflammatory infiltrate with a deep cystic appearance, surrounded by acute inflammatory infiltrate and necrotic material. Dermoscopy identified a foramen surrounded by dilated blood vessels and desquamation. A yellowish structure with a luminescent central ring was noted. Ultrasonography identified oval, hypoechoic, and hypovascular structures with inner echoic lines corresponding to cavities with debris and/or larval remains. Larvae were extracted before ultrasonography (Figure 1, b). Recommended treatment included topical antiseptic, occlusion of the infected area with paraffin, and 1% topical ivermectin; treatment resulted in incomplete resolution after 7 days. Furunculoid myiasis is more common in developing countries (1). Cases in Spain are usually imported, since the flies that produce this type of myiasis are not found locally. The species most frequently involved are D. hominis from Central and South America (botfly) and Cordylobia anthropophaga from the sub-Saharan region (tumbu fly) (2). We believe this was the first case in Spain imported from Guinea-Bissau. Several cases have been reported in Spain. Marco de Lucas et al. (3) reported a case in a Colombian male emigrant with multiple subependymal and intraventricular lesions, concentric blooming artifacts, and moderate hydrocephalus due to intracerebral myiasis. Another case was described by Arocha et al. (4). Central European countries continue to report new cases of imported furunculoid myiasis (5). D. hominis is a fly of the Oestridae family, approximately 1.5 cm long, yellowish-white in color, with a plumose edge (6). Larvae induce erythematous papules that sometimes ulcerate and resemble oils or large pustules, with a central orifice of about 1 mm, representing the larval respiratory pore. The lesions are usually painful (especially when larvae are still present) and pruritic, and produce sensations of movement under the skin. Lesions are located predominantly in exposed areas (7) and areas of contact with clothing and footwear, such as feet, buttocks, and external genitalia. Histopathology is not necessary for diagnosis, but usually reveals intense inflammatory infiltrate with abundant eosinophils surrounding larvae. (2) In our patient, ultrasound confirmed absence of living larvae within the cavity. D. hominis larvae show spontaneous movement in positive lesions and can be detected with ultrasound. Lesions in the hypodermis and dermis showed increased echogenicity of surrounding tissue, probably due to edema and inflammation (8). Diagnosis is established by comparing the lesion appearance with images of boils, abscesses, and inclusion of foreign body reaction cysts. Based on failed antibiotic therapy and travel to an endemic zone, myiasis should be considered in the differential diagnosis. Treatment consists of larval extraction through the respiratory orifice using pressure or a fine forceps or punch (9). Topical or oral ivermectin (10) can shorten the time to larval elimination. Physicians should be aware of this condition when travelers from endemic regions present with furuncular lesions, especially if movement is felt within the lesions or if lesions fail to heal. Myiasis is easily diagnosed based on clinical suspicion and epidemiological history, and is simple to treat.

Interleukin-2 and other cytokines in candidiasis: expression, clinical significance, and future therapeutic targets.

Susceptibility to Candida spp. infection is largely determined by the status of host immunity, whether immunocompromised/immunodeficient or immunocompetent. Interleukin-2 (IL-2), a potent lymphoid cell growth factor, is a four-α-helix bundle cytokine induced by activated T cells with two important roles: the activation and maintenance of immune responses, and lymphocyte production and differentiation. We reviewed the roles of cytokines as immune stimulators and suppressors of Candida spp. infections as an update on this continuously evolving field. We performed a comprehensive search of the Cochrane Central Register of Controlled Trials, Medline (PubMed), and Embase databases for articles published from March 2010 to March 2016 using the following search terms: interleukins, interleukin-2, Candida spp., and immunosuppression. Data from our own studies were also reviewed. Here, we provide an overview focusing on the ability of IL-2 to induce a large panel of trafficking receptors in skin inflammation and control T helper (Th)2 cytokine production in response to contact with Candida spp. Immunocompromised patients have reduced capacity to secrete Th1-related cytokines such as IL-2. The ability to secrete the Th1-related cytokine IL-2 is low in immunocompromised patients. This prevents an efficient Th1 immune response to Candida spp. antigens, making immunocompromised patients more susceptible to candidal infections.

Advances in Immunotherapy for Melanoma: A Comprehensive Review.

Melanomas are tumors originating from melanocytes and tend to show early metastasis secondary to the loss of cellular adhesion in the primary tumor, resulting in high mortality rates. Cancer-specific active immunotherapy is an experimental form of treatment that stimulates the immune system to recognize antigens on the surface of cancer cells. Current experimental approaches in immunotherapy include vaccines, biochemotherapy, and the transfer of adoptive T cells and dendritic cells. Several types of vaccines, including peptide, viral, and dendritic cell vaccines, are currently under investigation for the treatment of melanoma. These treatments have the same goal as drugs that are already used to stimulate the proliferation of T lymphocytes in order to destroy tumor cells; however, immunotherapies aim to selectively attack the tumor cells of each patient. In this comprehensive review, we describe recent advancements in the development of immunotherapies for melanoma, with a specific focus on the identification of neoantigens for the prediction of their elicited immune responses. This review is expected to provide important insights into the future of immunotherapy for melanoma.

HLA-DR association with the genetic susceptibility to develop ashy dermatosis in Mexican Mestizo patients.

BACKGROUND: Ashy dermatosis, also known as erythema dyschromicum perstans, is an acquired benign disease, characterized by blue-gray pigment patches with erythematous borders. The cause is still unclear, but probably has an immunologic basis. OBJECTIVE: The aim of this study was to determine gene frequencies of the HLA-DR alleles in Mexican patients with ashy dermatosis and compare them with ethnically matched healthy control subjects to reveal the genetic susceptibility to develop ashy dermatosis. METHODS: We included 23 consecutive patients with clinical and histopathologic confirmed diagnosis of erythema dyschromicum perstans. Patients and control subjects received a questionnaire to determine their ethnic origin and a peripheral blood sample was taken for DNA extraction. Finally, Genetic HLA-DRB1 was performed by polymerase chain reaction sequence-specific oligonucleotide reverse dot blot hybridization. RESULTS: Of the 23 patients included in this study, 65% were women and 35% were men. We observed that the disease was located in the trunk in 17 patients (74%) and the upper limbs in 15 patients (65%). The most frequent allele was HLA-DR4 (65%) (pC < 1 x 10(-6), odds ratio = 6.0, 95% confidence interval = 2.8-12.7) whereas in control subjects it was 23%. The most frequent molecular subtype in both patients and healthy control subjects was DRB1( *)0407, being statistically significant after comparing the two groups (pC < 1 x 10(-6), odds ratio = 7.0, 95% confidence interval = 3.1-15.8). LIMITATIONS: Since this is a disease strongly influenced by ethnicity, extrapolation to other ethnic groups is limited. CONCLUSIONS: Many factors influence the ethiopathogenesis of erythema dyschromicum perstans, but it is strongly suggested to have an important genetic susceptibility conferred by genes located within the major histocompatibility complex region.