Tongue lesion due to Cryptococcus neoformans as the first finding in an HIV-positive patient / Lesión lingual por Cryptococcus neoformans como primer hallazgo clínico en una paciente VIH positiva

BACKGROUND: Cryptococcosis is a severe universally distributed mycosis which mainly affects immunocompromised hosts. This mycosis is caused by yeasts of two species complex of the genus Cryptococcus: Cryptococcus neoformans and Cryptococcus gattii. Meningeal cryptococcosis is the most frequent clinical presentation of this disseminated mycosis. The oral mucosa involvement is extremely unusual. CASE REPORT: We present a case of cryptococcosis with an unusual clinical form. The patient was assisted because she had an ulcerated lesion on the lingual mucosa. Encapsulated yeasts compatible with Cryptococcus were found in microscopic exams of wet preparations from lingual ulcer clinical samples obtained for cytodiagnosis and mycological studies. Cryptococcus neoformans (C. neoformans var. grubii VNI) was isolated in culture. This patient did not know her condition of HIV seropositive before the appearance of the tongue lesion. CONCLUSIONS: The involvement of the oral mucosa is uncommon in this fungal infection, but is important to include it in the differential diagnosis in HIV positive patients

ANTECEDENTES: La criptococosis es una micosis grave de distribución universal que afecta principalmente a los huéspedes inmunodeficientes. Se han definido dos complejos de especies patógenas: Cryptococcus neoformans y Cryptococcus gattii. La meningoencefalitis es la presentación clínica más frecuente de esta micosis sistémica. La afectación de la mucosa oral es extremadamente rara. CASO CLÍNICO: Presentamos el caso de una paciente VIH positiva con una forma clínica inusual de criptococosis. La enferma presentaba una lesión ulcerada en la punta de la lengua. El examen microscópico en fresco de la escarificación y de la biopsia de esta lesión mostraron levaduras capsuladas compatibles con Cryptococcus. Se obtuvo Cryptococcus neoformans (C. neoformans var. grubii VNI) en los cultivos. La paciente conoció su estado inmunológico (infección por VIH) en el contexto de esta enfermedad oportunista. CONCLUSIONES: La afectación de la mucosa oral es poco común en esta infección fúngica, pero es importante incluirla en el diagnóstico diferencial en pacientes VIH positivos

Tongue lesion due to Cryptococcus neoformans as the first finding in an HIV-positive patient.

BACKGROUND: Cryptococcosis is a severe universally distributed mycosis which mainly affects immunocompromised hosts. This mycosis is caused by yeasts of two species complex of the genus Cryptococcus: Cryptococcus neoformans and Cryptococcus gattii. Meningeal cryptococcosis is the most frequent clinical presentation of this disseminated mycosis. The oral mucosa involvement is extremely unusual. CASE REPORT: We present a case of cryptococcosis with an unusual clinical form. The patient was assisted because she had an ulcerated lesion on the lingual mucosa. Encapsulated yeasts compatible with Cryptococcus were found in microscopic exams of wet preparations from lingual ulcer clinical samples obtained for cytodiagnosis and mycological studies. Cryptococcus neoformans (C. neoformans var. grubii VNI) was isolated in culture. This patient did not know her condition of HIV seropositive before the appearance of the tongue lesion. CONCLUSIONS: The involvement of the oral mucosa is uncommon in this fungal infection, but is important to include it in the differential diagnosis in HIV positive patients.

Problemas clínicos en micología médica: problema número 54 / Clinical problems in medical mycology: problem number 54

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A 26 year_old woman, who had been submmited to a classic cholecystectomy for a lithic cholecystitis, was admitted in the Hepathology Unit of the F. J. Muniz Hospital of Buenos Aires City, due to persistent jaundice, weight loss, asthenia, arterial hypotension, ascites and periumbilical ulcer. These skin lesions were located under an adhesive tape which was around a Kehr tube. Laboratory studies showed anemia, hyperbilirrubinemia, increased level of hepatic enzymes and a positive anti-mitochondrial antibodies test 1/80. The diagnosis of her liver disease was autoimmune hepatitis and the patient received corticosteroid treatment by oral route. The microbiological study of the skin lesions showed hyaline, wide, non_septate hyphae in the microscopic study, and Rhizopus arrhizus was isolated in cultures. Colloidal dispersion of amphotericin B at a daily dose of 5 mg/kg intravenously was administered and a surgical debridement of the cutaneous lesions was done. Skin lesions improved with this treatment, but her hepatic condition turned worse and evolved to a fatal hepatic insufficiency. She could not receive a liver transplant due to the lack of a compatible donor

Nursing Professionals' Attitudes, Strategies, and Care Practices Towards Death: A Systematic Review of Qualitative Studies.

PURPOSE: To explore the attitude of nursing professionals towards death. DESIGN: Systematic qualitative review methods were used. METHODS: A search was conducted in the PubMed, Web of Science, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and CUIDEN databases. This study included 17 articles. FINDINGS: Thirteen categories emerged, which were grouped into three themes: meanings and feelings during the dying process; coping strategies in the face of death; and the importance of training, experience, and providing a dignified death. In the different accounts of the participants, it was found that death had a large negative emotional impact on them, that the participants complained about the lack of previous training in the care of dying patients, and that avoiding these complex situations was one of the strategies most commonly used by professionals to face the death of a patient. CONCLUSIONS: The lack of training in the basic care of terminally ill patients, as well as today's preconceived negative idea about death, both cause health professionals to experience situations of great stress and frustration resulting, on many occasions, in resorting to avoidance of these situations, thus preventing dying with dignity. CLINICAL RELEVANCE: In this article, we explore the consequences of this process for nursing professionals, common coping strategies, and possible areas for improvement, such as the need for the training of nursing professionals in the care of terminally ill patients and their families.

Role of α-glucan-induced oxygen species in dendritic cells and its impact in immune response against tuberculosis.

With 10 million new cases and three million deaths estimated to occur yearly ̶ more than any time in history ̶ tuberculosis (TB) remains the single most widespread and deadly infectious disease. Until recently, it was thought that both latent and active TB was primarily related to host factors. Nonetheless, the participation of bacterial factors is becoming increasingly evident. Minimal variations in genes related to Mycobacterium tuberculosis (Mtb) virulence and pathogenesis can lead to marked differences in immunogenicity. Dendritic cells (DC) are professional antigen presenting cells whose maturation can vary depending on the cell wall composition of each particular Mtb strain being critical for the onset of the immune response against Mtb. Here we evaluated the role played by α-glucan, in the endogenous production of reactive oxygen species, ROS, and the impact on DC maturation and function. Results showed that α-glucans on Mtb induce ROS production leading to DC maturation and lymphocyte proliferation. Even more, α-glucans induced Syk activation but were not essential in non-opsonized phagocytosis. In summary, α-glucans of Mtb participates in ROS production and the subsequent DC maturation and antigen presentation, suggesting a relevant role of α-glucans for the onset of the protective immune response against TB.

Reactive oxygen species production by human dendritic cells involves TLR2 and dectin-1 and is essential for efficient immune response against Mycobacteria.

Tuberculosis remains the single largest infectious disease with 10 million new cases and two million deaths that are estimated to occur yearly, more than any time in history. The intracellular replication of Mycobacterium tuberculosis (Mtb) and its spread from the lungs to other sites occur before the development of adaptive immune responses. Dendritic cells (DC) are professional antigen-presenting cells whose maturation is critical for the onset of the protective immune response against tuberculosis disease and may vary depending on the nature of the cell wall of Mtb strain. Here, we describe the role of the endogenous production of reactive oxygen species (ROS) on DC maturation and expansion of Mtb-specific lymphocytes. Here, we show that Mtb induces DC maturation through TLR2/dectin-1 by generating of ROS and through Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Non-integrin (DC-SIGN) in a ROS independently manner. Based on the differences observed in the ability to induce DC maturation, ROS production and lymphocyte proliferation by those Mtb families widespread in South America, i.e., Haarlem and Latin American Mediterranean and the reference strain H37Rv, we propose that variance in ROS production might contribute to immune evasion affecting DC maturation and antigen presentation.

Outbreaks of Mycobacterium tuberculosis MDR strains differentially induce neutrophil respiratory burst involving lipid rafts, p38 MAPK and Syk.

BACKGROUND: Neutrophils (PMN) are the first cells to infiltrate the lung after infection, and they play a significant protective role in the elimination of pathogen, by releasing preformed oxidants and proteolytic enzymes from granules and generating ROS, thus limiting inflammation by succumbing to apoptosis. In a previous study, we found marked differences in ROS-induced apoptosis between two Mycobacterium tuberculosis (Mtb) strains, M and Ra, representative of widespread Mtb families in South America, i.e. Haarlem and Latin-American Mediterranean (LAM), being strain M able to generate further drug resistance and to disseminate aggressively. METHODS: In this study we evaluate the nature of bacteria-PMN interaction by assessing ROS production, apoptosis, lipid raft coalescence, and phagocytosis induced by Mtb strains. RESULTS: Dectin-1 and TLR2 participate in Mtb-induced ROS generation and apoptosis in PMN involving p38 MAPK and Syk activation with the participation of a TLR2-dependent coalescence of lipid rafts. Further, ROS production occurs during the phagocytosis of non-opsonized bacteria and involves α-glucans on the capsule. In contrast, strain M lacks the ability to induce ROS because of: 1) a reduced phagocytosis and 2) a failure in coalescence of lipid raft. CONCLUSIONS: The differences in wall composition could explain the success of some strains which stay unnoticed by the host through inhibition of apoptosis and ROS but making possible its replication inside PMN as a potential evasion mechanism. Innate immune responses elicited by Mtb strain-to-strain variations need to be considered in TB vaccine development.

Mycobacterium tuberculosis impairs dendritic cell response by altering CD1b, DC-SIGN and MR profile.

During a chronic infection such as tuberculosis, the pool of tissue dendritic cells (DC) must be renewed by recruitment of both circulating DC progenitors and monocytes (Mo). However, the microenvironment of the inflammatory site affects Mo differentiation. As DC are critical for initiating a Mycobacterium tuberculosis-specific T-cell response, we argue that interference of M. tuberculosis with a correct DC generation would signify a mechanism of immune evasion. In this study, we showed that early interaction of γ-irradiated M. tuberculosis with Mo subverts DC differentiation in vitro. We found that irradiated M. tuberculosis effect involves (1) the loss of a significant fraction of monocyte population and (2) an altered differentiation process of the surviving monocyte subpopulation. Moreover, in the absence of irradiated M. tuberculosis, DC consist in a major DC-specific intercellular adhesion molecule 3-grabbing non-integrin receptor (DC-SIGN(high))/CD86(low) and minor DC-SIGN(low)/CD86(high) subpopulations, whereas in the presence of bacteria, there is an enrichment of DC-SIGN(low)/CD86(high) population. Besides, this population enlarged by irradiated M. tuberculosis, which is characterized by a reduced CD1b expression, correlates with a reduced induction of specific T-lymphocyte proliferation. The loss of CD1molecules partially involves toll-like receptors (TLR-2)/p38 MAPK activation. Finally, several features of Mo, which have been differentiated into DC in the presence of irradiated M. tuberculosis, resemble the features of DC obtained from patients with active tuberculosis. In conclusion, we suggest that M. tuberculosis escapes from acquired immune response in tuberculosis may be caused by an altered differentiation into DC leading to a poor M. tuberculosis-specific T-cell response.

Patients with multidrug-resistant tuberculosis display impaired Th1 responses and enhanced regulatory T-cell levels in response to an outbreak of multidrug-resistant Mycobacterium tuberculosis M and Ra strains.

In Argentina, multidrug-resistant tuberculosis (MDR-TB) outbreaks emerged among hospitalized patients with AIDS in the early 1990s and thereafter disseminated to the immunocompetent community. Epidemiological, bacteriological, and genotyping data allowed the identification of certain MDR Mycobacterium tuberculosis outbreak strains, such as the so-called strain M of the Haarlem lineage and strain Ra of the Latin America and Mediterranean lineage. In the current study, we evaluated the immune responses induced by strains M and Ra in peripheral blood mononuclear cells from patients with active MDR-TB or fully drug-susceptible tuberculosis (S-TB) and in purified protein derivative-positive healthy controls (group N). Our results demonstrated that strain M was a weaker gamma interferon (IFN-gamma) inducer than H37Rv for group N. Strain M induced the highest interleukin-4 expression in CD4+ and CD8+ T cells from MDR- and S-TB patients, along with the lowest cytotoxic T-lymphocyte (CTL) activity in patients and controls. Hence, impairment of CTL activity is a hallmark of strain M and could be an evasion mechanism employed by this strain to avoid the killing of macrophages by M-specific CTL effectors. In addition, MDR-TB patients had an increased proportion of circulating regulatory T cells (Treg cells), and these cells were further expanded upon in vitro M. tuberculosis stimulation. Experimental Treg cell depletion increased IFN-gamma expression and CTL activity in TB patients, with M- and Ra-induced CTL responses remaining low in MDR-TB patients. Altogether, these results suggest that immunity to MDR strains might depend upon a balance between the individual host response and the ability of different M. tuberculosis genotypes to drive Th1 or Th2 profiles.