Photodynamic therapy in the coadjuvant treatment of Sporothrix schenckii complex

INTRODUCTION

Sporotrichosis, a zoonosis caused by animal, mainly cat, scratches or bites, is caused by fungi belonging to the Sporothrix complex. Treatment usually consists in antifungal administration, although treatment failure and hepatotoxicity reports have been noted. Alternative sporotrichosis treatment methods, such as antimicrobial photodynamic therapy (aPDT), may, therefore, be indicated.

CASE REPORT

In this context, this study followed a 56-year-old male renal transplanted patient displaying disseminated sporotrichosis, presenting erythematous skin lesions with ulcerated backgrounds and hardened consistency on the nose, oral and scalp. The lesions were present for about 2 months and the patient coexisted with cats. Intravenous amphotericin B administration was initiated, and immunosuppression was suspended. Seven aPDT sessions were also performed in 48 h intervals on the oral lesions, employing 0.01% methylene blue gel as the photosensitizing agent. After the 4th aPDT session, the patient was discharged, amphotericin B administration was suspended, and the treatment was continued with itraconazole, without immunosuppression. Red laser was applied to the oral lesions after the 7th aPDT session. Significant lesion improvement was observed after the final aPDT session and complete palate lesion repair was noted after two red laser sessions.

CONCLUSION

These findings indicate that aPDT is a valuable strategy as an adjunct sporotrichosis treatment.

Response of Cytokines and Hydrogen Peroxide to Sporothrix schenckii Exoantigen in Systemic Experimental Infection

The response of hydrogen peroxide (H2O2) and cytokines during an experimental sporotrichosis in male Swiss mice was assessed over a period of 10 weeks by monitoring macrophage activation challenged with exoantigen (ExoAg) from the fungus Sporothrix schenckii. The studied endpoints were: H2O2 production, fungal burden at spleen, apoptosis in peritoneal macrophages, and IL-1β, IL-6, IL-2, IL-10 production. During the two first weeks of infection was observed low burden of yeast in spleen and high response of H2O2, IL-2, and IL-1β. The weeks of highest fungal burden (fourth-sixth) coincided with major apoptosis in peritoneal macrophages, normal production of IL-6 and lower production of H2O2, IL-2, and IL-1β, suggesting a role for these three last in the early control of infection. On the other hand, IL-1β (but not IL-6) was recovered since the sixth week, suggesting a possible role in the late phase of infection, contributing to the fungal clearance in conjunction with the specific mechanisms. The IL-10 was elevated until the sixth, principally in the second week. These results evidences that ExoAg is involved in the host immune modulation, influencing the S. Schenckii virulence, and its role is related with the time of the infection in the model used.

The impact of sporotrichosis in HIV-infected patients: a systematic review

Sporotrichosis is a fungal infection of man and animals caused by Sporothrix complex. It usually presents as a lymphocutaneous form, but disseminated disease may occur. Given the paucity of data about HIV/AIDS and sporotrichosis co-infection, a systematic review of reported cases of HIV-associated sporotrichosis found via Pubmed (1984-2013) was done. A total of 39 papers were included, and 58 patients' data analyzed. Thirty-three (56.9 %) cases were from Brazil and 18 (31 %) from the USA. Patients' mean age was 37.8 ± 10.4 years; males predominated (84.5 %). The median CD4(+) cell count was 97 cells/mm(3). The most common clinical forms were disseminated and disseminated cutaneous with 33 (56.9 %) and 10 (17.5 %) patients, respectively. There was a correlation between CD4(+) count and clinical categories (p = 0.002). Mortality was 30 % and there was a correlation between central nervous system involvement and death (p < 0.001).

Sporotrichosis: a forgotten disease in the drug research agenda

Potassium iodide was discovered in the 19th century and still remains as one of the more effective and most prescribed treatments for sporotrichosis. No new drugs have been evaluated in large randomized clinical trials in comparison with standard or alternative treatments for sporotrichosis during the last decades. The emergence of disseminated sporotrichosis in AIDS patients has uncovered the need for more effective treatments. Sporotrichosis is only a public health problem in a few geographical areas, mostly located in developing countries; and its usually harmless history could explain the limited investment in sporotrichosis treatment research. Better understanding of the virulence factors, such as the melanization process, could reveal new potential drug targets.

Dendritic cell are able to differentially recognize Sporothrix schenckii antigens and promote Th1/Th17 response in vitro

Sporotrichosis is a disease caused by the dimorphic fungus Sporothrix schenckii. The main clinical manifestations occur in the skin, however the number of systemic and visceral cases has increased, especially in immunocompromised patients. Dendritic cells (DCs) are highly capable to recognize the fungus associated data and translate it into differential T cells responses both in vivo and in vitro. Although, the mechanisms involved in the interaction between DCs and S. schenckii are not fully elucidated. The present study investigated the phenotypic and functional changes in bone marrow dendritic cells (BMDCs) stimulated in vitro with the yeast form of S. schenckii or exoantigen (ExoAg) and its ability to trigger a cellular immune response in vitro. Our results demonstrated that the live yeast of S. schenckii and its exoantigen, at a higher dose, were able to activate BMDCs and made them capable of triggering T cell responses in vitro. Whereas the yeast group promoted more pronounced IFN-γ production rather than IL-17, the Exo100 group generated similar production of both cytokines. The exoantigen stimulus suggests a capability to deviate the immune response from an effector Th1 to an inflammatory Th17 response. Interestingly, only the Exo100 group promoted the production of IL-6 and a significant increase of TGF-β, in addition to IL-23 production. Interestingly, only Exo100 group was capable to promote the production of IL-6 and a significant increase on TGF-β, in addition with IL-23 detection. Our results demonstrated the plasticity of DCs in translating the data associated with the fungus S. schenckii and ExoAg into differential T cell responses in vitro. The possibility of using ex vivo-generated DCs as vaccinal and therapeutic tools for sporotrichosis is a challenge for the future.

Sporotrichosis in HIV-infected patients: report of 21 cases of endemic sporotrichosis in Rio de Janeiro, Brazil

Sporotrichosis is endemic in Rio de Janeiro, Brazil, and cases have been reported to be associated with HIV. This article describes the clinical manifestations and evolution of sporotrichosis in HIV-positive patients and constitutes the largest case series reported to date. There were 21 HIV-positive patients with sporotrichosis diagnosed by the recovery of the etiologic agent from 1999-2009. Sixteen patients (76.2%) were men and five (23.8%) were women, with a mean age of 41.2 years. Seven of these individuals were previously unaware of their HIV infection. Mean CD4 count was 346.4 cells/μl. The most frequent clinical presentations of sporotrichosis in these patients were the lymphocutaneous and disseminated form (seven patients each, 33.3%), followed by the widespread cutaneous form in five (23.8%), and fixed form in the remaining two (9.5%). In patients with the disseminated forms, clinical manifestations involved the skin in six, mucosa (nasal, oral, or conjunctival) in four, bone in two, and meninges in two. Eleven (52.4%) patients received itraconazole and eight (38.1%) amphotericin B contributing to an overall cure rate of 81%. Spontaneous cure was observed in one patient. The clinical forms of sporotrichosis varied according to the patients' immune status. The results demonstrate the importance of sporotrichosis as an opportunistic infection associated with AIDS in countries where the mycosis occurs.

Detrimental role of endogenous nitric oxide in host defence against Sporothrix schenckii

We earlier demonstrated that nitric oxide (NO) is a fungicidal molecule against Sporothrix schenckii in vitro. In the present study we used mice deficient in inducible nitric oxide synthase (iNOS-/-) and C57BL/6 wild-type (WT) mice treated with Nomega-nitro-arginine (Nitro-Arg-treated mice), an NOS inhibitor, both defective in the production of reactive nitrogen intermediates, to investigate the role of endogenous NO during systemic sporotrichosis. When inoculated with yeast cells of S. schenckii, WT mice presented T-cell suppression and high tissue fungal dissemination, succumbing to infection. Furthermore, susceptibility of mice seems to be related to apoptosis and high interleukin-10 and tumour necrosis factor-alpha production by spleen cells. In addition, fungicidal activity and NO production by interferon-gamma (IFN-gamma) and lipopolysaccharide-activated macrophages from WT mice were abolished after fungal infection. Strikingly, iNOS-/- and Nitro-Arg-treated mice presented fungal resistance, controlling fungal load in tissues and restoring T-cell activity, as well as producing high amounts of IFN-gamma Interestingly, macrophages from these groups of mice presented fungicidal activity after in vitro stimulation with higher doses of IFN-gamma. Herein, these results suggest that although NO was an essential mediator to the in vitro killing of S. schenckii by macrophages, the activation of NO system in vivo contributes to the immunosuppression and cytokine balance during early phases of infection with S. schenckii.

Oro-facial lesions and CD4 counts associated with HIV/AIDS in an adult population in Oyo State, Nigeria

OBJECTIVE

The objective of this study was to define the oro-facial lesions associated with Human Immunodeficiency Virus (HIV)/Acquired Immune Deficiency Syndrome (AIDS) in an adult population in Oyo state, Nigeria and to relate these with the level of immune suppression as measured by the CD4 counts.

MATERIALS AND METHOD

The study population consisted of 679 consecutive subjects who were seen at the state-owned blood bank. Information on demography, medical and medication histories were obtained. Oro-facial examinations were carried out according to Greenspan et al [Oral Surg Oral Med Oral Pathol (1992)73:142-144]. HIV sero-prevalence status was determined for all patients. CD4+ T-lymphocyte count was carried out for those sero-positive for HIV and 31 randomly selected HIV-negative subjects. Data were analyzed using the chi-square test, Fisher's exact test, Student's t-test and odds ratio where appropriate.

RESULTS

Eighty-one (11.9%) of the entire study sample were confirmed HIV positive. The prevalence of specific oral lesions by HIV sero-status revealed that pseudomembranous oral candidiasis and angular cheilitis occurred significantly and more frequently in HIV-positive subjects (33.3 and 21% respectively) than those who were HIV negative (4.3 and 1.8% respectively, P < 0.05). The mean CD4 count of the HIV-positive subjects was 452 cells mm(-3), s.d. 137, while it was 602 cells mm(-3), s.d. 251, for the HIV negatives. The difference was statistically significant (P = 0.000). Forty-four (66.7%) subjects with CD4 counts <500 cells mm(-3) had oro-facial lesions whereas among those with CD4 counts >500 cells mm(-3) only 22 (33.3%) had oro-facial lesions (OR = 4.57).

CONCLUSION

The type of oro-facial lesions most commonly associated with HIV/AIDS in Oyo state, Nigeria, has been shown to be pseudomembranous oral candidiasis. This was followed by angular cheilitis. These lesions, although found in HIV-negative subjects, were in a lower proportion as compared with HIV-positive subjects. Mean CD4 counts were lower in HIV-positive subjects and this was associated with greater prevalence of oro-facial candidiasis and angular cheilitis.

Development of an enzyme-linked immunosorbent assay for the serodiagnosis of several clinical forms of sporotrichosis

We performed a serological study with sera from 92 patients with confirmed sporotrichosis registered between 1999 and 2004 in two hospitals in Rio de Janeiro State, Brazil. The clinical presentation of sporotrichosis was distributed as follows: lymphocutaneous, 67%; fixed cutaneous, 23%; disseminated cutaneous, 8%; and extracutaneous, 2%. Sera were assayed by ELISA against a cell wall antigen of Sporothrix schenckii, SsCBF, that we have previously described. The cross-reactivity was determined with 77 heterologous sera. The serological test showed a sensitivity of 90% and a global efficiency of 86%. A group of 55 patients with several clinical presentations of sporotrichosis was clinically and serologically followed-up for at least 6 months. We observed by ELISA data a decrease in the antibody serum titers which correlated with the progress in healing. An HIV-positive patient with meningeal sporotrichosis was serologically followed-up for over 2 years. Serum and cerebrospinal fluid specimens were examined and significant antibodies levels against the antigen SsCBF were detected. Our results strongly suggest that this serological test is valuable for the differential diagnosis and follow-up of all clinical forms of sporotrichosis.