A infecção em receptores de transplante de células-tronco hematopoéticas (TCTH) está relacionada a altas taxas de morbidade e mortalidade. O tipo de transplante, a fonte de célula-tronco hematopoética, a utilização de doadores alternativos e outras medidas relacionadas ao procedimento influenciam diretamente no tipo e na intensidade da imunossupressão, modificando o risco de desenvolver uma infecção. Nesta seção são discutidas as estratégias para monitorização, diagnóstico e tratamento das infecções em receptores de TCTH em três fases: na fase pré-transplante, durante a fase de neutropenia, e na fase pós-pega do enxerto.

Infectious complications following stem cell transplantation are frequent and associated with high morbidity and mortality. Several factors related to the transplant procedure, such as type of transplant, the source of stem cells, the utilization of alternative donors are important determinants of the immune status of the host, and impact on the risk of infection. In this section we will discuss the different approaches for monitoring patients at risk and diagnosing and treating infectious complications in three time periods: before transplant, during neutropenia, and after engraftment.

Histiocitose de células de Langerhans é uma doença rara de causa desconhecida, caracterizada pela proliferação de células histiocitárias (células de Langerhans). Representa significativa dificuldade diagnóstica por apresentar amplo espectro clínico, variando desde uma lesão solitária até uma enfermidade multissistêmica. Pode ser confirmada por estudo imunoistoquímico. O tratamento depende da extensão do processo, podendo ser necessária quimioterapia sistêmica.

Langerhans cell histiocytosis is a rare disease of unknown cause, characterized by the proliferation of histiocytic cells (Langerhans cells). Its diagnosis is especially difficult due to its wide clinical spectrum, ranging from a single lesion to a multisystemic disorder. Diagnosis may be confirmed by means of an immunohistochemical study. Treatment depends upon the severity of the disease, and systemic chemotherapy may be needed.

O vírus sincicial respiratório (RSV) é considerado uma causa importante de morbi-mortalidade em pacientes submetidos ao transplante de células-tronco hematopoéticas (TCTH). Mesmo com o uso da ribavirina inalatória (RI), as taxas de mortalidade são de 30% a 40% . O objetivo deste trabalho foi analisar o perfil dos pacientes infectados pelo RSV e a eficácia do tratamento com RI. Realizou-se uma análise retrospectiva de 59 pacientes submetidos ao TCTH com infecção confirmada pelo RSV (métodos de IFI ou PCR) entre 02/1991 e 02/2008. A RI foi administrada por 12 horas, na dose de 5 g diluída 200 ml de água destilada, por cinco dias. Quinze pacientes apresentaram infecções (TRI) do trato respiratório inferior e 44 pacientes apresentaram infecções (TRS) de vias aéreas superiores. No grupo tratado (n=50), quarenta apresentaram infecções no TRS versus dez TRI; no grupo não tratado, quatro TRS versus cinco TRI. Foram constatados vinte óbitos (33,8%), sendo que 13 desses pacientes (65% dos óbitos) tiveram suas mortes relacionadas ao RSV. Dentre estes, nove pacientes foram a óbito antes da instituição da RI como terapia padrão. A sobrevida global (SG) de todos os pacientes foi de 8,3 meses, sendo 66% para o grupo que utilizou RI versus 11,1% no grupo não tratado(p=0,001). No entanto, a SG foi inferior nos pacientes que apresentaram infecções no TRI (37,5%) quando comparadas às infecções do TRS (65,1%), p=0,007. No modelo de regressão de Cox, a única variável independente encontrada foi o tratamento com RI (p=0,001).

Respiratory syncytial virus (RSV) causes significant mortality in patients submitted to SCT. Despite the use of ribavirin aerosols (RA), mortality rates are still between 30 and 40% in many centers. The objective of this study was to analyze the clinical course and outcome of 59 patients who developed RSV infections after SCT in a single institution. In this retrospective analysis, the diagnosis of RSV infection was confirmed in 59 patients submitted to HSCT. RA was administrated during 12 hours at a dose of 5g diluted in 200 mL of distillated water, for 5 days. Fifteen patients presented with upper respiratory tract (URT) infection and 44 patients presented with lower respiratory tract (LRT) infection. In the group of patients who received RA (n=50), 40 had URT infections and 10 had LRT infections. In patients who did not receive RA, 3 had URT infections and 6 had LRT infections. Twenty patients died (33.8%) with the main cause of death of 13 patients being RSV infection (all these patients required mechanical ventilation). Nine patients died before RA therapy became standard treatment for RSV (before 1992). The overall survival of patients treated with RA was 66%. However, the overall survival was lower in patients who had LRT infections (37.5%) compared with those who had URT infections (67.5% - p=0.007). In the multivariate analysis, only the use of RA affected overall survival (p=0.001).

Community-Acquired Pneumonia (CAP) is a major public health problem. In Brazil it has been estimated that 2,000,000 people are affected by CAP every year. Of those, 780,000 are admitted to hospital, and 30,000 have death as the outcome. This is an open-label, non-comparative study with the purpose of evaluating efficacy, safety, and tolerability levels of IV azithromycin (IVA) and IV ceftriaxone (IVC), followed by oral azithromycin (OA) for the treatment of inpatients with mild to severe CAP. Eighty-six patients (mean age 56.6 ± 19.8) were administered IVA (500mg/day) and IVC (1g/day) for 2 to 5 days, followed by AO (500mg/day) to complete a total of 10 days. At the end of treatment (EOT) and after 30 days (End of Study - EOS) the medication was evaluated clinically, microbiologically and for tolerability levels. Out of the total 86-patient population, 62 (72.1%) completed the study. At the end of treatment, 95.2% (CI95: 88.9% - 100%) reported cure or clinical improvement; at the end of the study, that figure was 88.9% (CI95: 74.1% - 91.7%). Out of the 86 patients enrolled in the study, 15 were microbiologically evaluable for bacteriological response. Of those, 6 reported pathogen eradication at the end of therapy (40%), and 8 reported presumed eradication (53.3%). At end of study evaluation, 9 patients showed pathogen eradication (50%), and 7 showed presumed eradication (38.89%). Therefore, negative cultures were obtained from 93.3% of the patients at EOT, and from 88.9% at the end of the study. One patient (6.67% of patient population) reported presumed microbiological resistance. At study end, 2 patients (11.11%) still reported undetermined culture. Uncontrollable vomiting and worsening pneumonia condition were reported by 2.3% of patients. Discussion and Conclusion Treatment based on the administration of IV azithromycin associated to ceftriaxone and followed by oral azithromycin proved to be efficacious and well-tolerated in the treatment of Brazilian inpatients with CAP.

O diabetes mellitus (DM) é uma doença de alta prevalência nas sociedades modernas, na maioria das vezes com tratamento inadequado ou ausente. Apesar de geralmente considerado como fator de risco independente para ocorrência e gravidade de infecções em geral, o DM não apresenta evidência clínica forte de sua relação com infecção. Observa-se, porém, uma maior ocorrência de certas infecções em pacientes com DM, com curso menos favorável para algumas delas. Há também tipos de infecção quase exclusivos de pacientes com DM. Experimentalmente, observa-se depressão da atividade dos neutrófilos, menor eficiência da imunidade celular, alteração dos sistemas antioxidantes e menor produção de interleucinas. Com relação às infecções comuns, as que envolvem o trato respiratório não têm comprovadamente maior gravidade em pacientes com DM, exceção feita ao pneumococo - por isso a recomendação para sua vacinação contra S. pneumoniae e influenza. Quanto ao trato urinário, há maior ocorrência de bacteriúria assintomática em mulheres com DM, com maiores índices de pielonefrite, necrose papilar, abscesso perinéfrico, pielonefrite xantogranulomatosa, e cistite e pielonefrite gangrenosas. Periodontite e infecções de partes moles são também mais comuns no DM. Cada tipo de infecção é associado a germes típicos, e seu conhecimento é fundamental para um tratamento inicial adequado. As infecções quase exclusivas de pacientes com DM incluem otite externa maligna, mucormicose rinocerebral, colecistite gangrenosa e o somatório de alterações que caracterizam o pé diabético. O conhecimento destas infecções assume maior importância por requererem freqüentemente uma abordagem multidisciplinar, envolvendo endocrinologistas, infectologistas, cirurgiões vasculares e nefrologistas, dentre outros.

Diabetes mellitus (DM) is a highly prevalent disease in modern societies, most of the times being either inappropriately treated or not treated at all. Though generally considered to be an independent risk factor for the occurrence and severity of infections in general, DM has not been clinically proven to have any strong association with infection. There are, however, certain infections that are more common in DM, sometimes with a less favorable course than in non-diabetics. Other types of infection affect almost exclusively patients with DM. Experimentally, DM patients have a depressed neutrophil activity, a less effective cell mediated immunity, altered antioxidant systems and diminished interleukin synthesis. Regarding common infections, those affecting the respiratory tract have not been proven to be more serious in DM patients, with the exception of S. pneumoniae infections - thus the recommendation to vaccinate them against pneumococcus and influenza. As for urinary tract infections, bacteriuria takes place more commonly in women with DM, more frequently complicated by pyelonephritis, papillary necrosis, xanthogranulomatous pyelonephritis and gangrenous cystitis/ pyelonephritis. Periodontitis and soft-tissue infections are also more common in DM. Each specific infection is associated with typical microbes, and their knowledge is essential for an appropriate initial treatment. The nearly exclusively DM-related infections include malignant external otitis, rhinocerebral mucormycosis, gangrenous cholecystitis, and the sum of alterations referred to as "diabetic foot". The general knowledge of these infections assumes great importance since they often require a multidisciplinary approach, involving endocrinologists, infectologists, nephrologists and vascular surgeons, among others.