HCMV UL97 phosphotransferase gene mutations may be associated with antiviral resistance in immunocompromised patients in Belém, PA, Northern Brazil

Abstract INTRODUCTION: Human cytomegalovirus is one of the causes of opportunist infections in immunocompromised patients, and is triggered by factors such as state of viral latency, weakened immune responses, and development of antiviral resistance to ganciclovir, the only drug offered by the public health system in Brazil to treat the infection. The goal of this study was to identify mutations that may be associated with antiviral resistance in immunocompromised patients. METHODS: Molecular analysis was performed in 82 blood samples and subjected to genomic DNA extraction by a silica-based method. Three sequences of the HCMV UL97 gene, which encodes a phosphotransferase protein required for activation of ganciclovir, were amplified by polymerase chain reaction. Pyrosequencing methods were applied to one external 2096-bp segment DNA and two internal sequences between nucleotides 1087 to 1828 to detect mutations in this gene. RESULTS: Approximately 10% of sequences contained mutations between nucleotides 377 and 594, in conserved regions of the UL97 gene, leading to amino acid changes. Eleven coding mutations were identified, including changes leading to amino acid substitutions, E596K and S604F, which were observed in 100% of samples and are described for the first time in Brazil. In addition, one mutation (A594V) that is associated with ganciclovir resistance was detected in a kidney transplant patient. CONCLUSIONS: Further studies to detect mutations associated with HCMV resistance to antiviral drugs are required to demonstrate the need to increase the variety and availability of drugs used to treat viral infections in the public health care system in Brazil.

The use of ozonated water and 0.2% chlorhexidine in the treatment of periodontitis patients: A clinical and microbiologic study.

Background: The development of periodontal disease has been thought to be associated with several restricted members of the oral anaerobic species, such as black-pigmented Porphyromonas species and Actinobacillus actinomycetemcomitans (Aa), in the subgingival environment. Apart from bacteria, certain viruses and fungi that are associated with periodontal disease are also present in the subgingival plaque . Materials and Methods: A randomized, double-blind, crossover split-mouth design was performed. A total of 16 patients suffering from generalized chronic periodontitis were selected for the study. The study period of 18 days was divided into two time-intervals, i.e. baseline (0 days) to 7 th day, with a washout period of 4 days followed by a second time interval of 7 days. The use of ozone and chlorhexidine gluconate (CHX) irrigation was randomized. Both the patient and the clinician evaluating the clinical parameters were blinded regarding the type of irrigation used. Results: The interpretation of clinical and microbial data is from baseline to 7 th day. A higher percentage of plaque index (12%), gingival index (29%) and bleeding index (26%) reduction was observed using ozone irrigation as compared to chlorhexidine. The percentile reduction of Aa (25%) using ozone was appreciable as compared to no change in Aa occurrence using chlorhexidine. By using O 3 and chlorhexidine, there was no antibacterial effect on Porphyromonas gingivalis (Pg) and Tannerella forsythensis. The antifungal effect of ozone from baseline (37%) to 7 th day (12.5%) was pronounced during the study period, unlike CHX, which did not demonstrate any antifungal effect. Conclusion: Ozone may be considered as an alternative management strategy due to its powerful ability to inactivate microorganisms. Also, there is growing evidence that ozone can be employed as a useful therapeutic agent in both dentistry and medicine.

Búsqueda de mutaciones en el gen UL 97 asociadas a resistencia a ganciclovir en citomegalovirus obtenidos desde muestras biológicas de pacientes chilenos / Presence of mutations associated with ganciclovir resistance in cytomegalovirus UL 97 gene

Background: Long term use of ganciclovir (GCV) is associated with acquired resistance to it. Ninety percent of the responsible mutations occur in cytomegalovirus (CMV) UL 97 gene. Aim: To search for these mutations, comparing nucleotide sequences of CMV-positive samples from post transplant and immunocompromised patients receiving GCV, with sequences of CMV isolates obtained from subjects not exposed to the drug. Patients and Methods: Codons 440 to 465 of gene UL 97, in-cluding the most common mutations causing resistance to GCV, were amplifed in 33 plasma samples from patients exposed to GCV and in 15 urine samples of newborns. Both populations and their nucleotide sequences were compared with the prototype strain CMV AD169. Results: Samples of exposed patients had multiple mutations but only one had a mutation associated with clinical resistance (M460I). Eight subjects had the D605E mutation, whose role in resistance is controversial. The remaining 150 mutations were silent mutations. Conclusions: A low frequency of mutations associated with CMV resistance to GCV was found in these exposed and unexposed samples. These mutations may refect coexistence of multiple genetic variants of CMV. The absence of clinical expression of resistance, even with these mutations, can be explained by the use of GCV for a shorter lapse than that associated with the appearance of resistance.

Cytomegalovirus Ventriculoencephalitis after Unrelated Double Cord Blood Stem Cell Transplantation with an Alemtuzumab-containing Preparative Regimen for Philadelphia-positive Acute Lymphoblastic Leukemia

Despite the prophylaxis and preemptive strategies using potent antiviral agents, cytomegalovirus (CMV) remains a major infectious cause of morbidity and mortality in allogeneic stem cell transplantation (SCT) recipients. Delayed immune reconstitution after SCT, such as cord blood and T-cell depleted SCT with the use of alemtuzumab, has been associated with an increased frequency of CMV disease as well as CMV reactivation. CMV disease involving central nervous system is an unusual presentation in the setting of SCT. We report a case of CMV ventriculoencephalitis after unrelated double cord blood SCT with an alemtuzumab-containing preparative regimen for Philadelphia-positive acute lymphoblastic leukemia.

Evolución de la infección por citomegalovirus en trasplantados renales / Evolution of cytomegalovirus infection in renal transplant recipients

Background: The incidence of cytomegalovirus infection or reactivation is 8 times more frequent in transplant recipients than in the general population. Aim: To evaluate the prevalence and usefulness of different diagnostic techniques for cytomegalovirus infection in renal transplant recipients. Patients and methods: Twenty nine renal transplant recipients were followed for at least five months. Cytomegalovirus infection was assessed by the presence of serum antibodies against the virus using ELISA and viral detection in urine and lymphocytes, using classical viral isolation, shell vial assay, and detection of viral genome by polymerase chain reaction. Results: Prior to transplantation, 23 of 27 patients had IgG type anti cytomegalovirus antibodies. In 40 percent, IgM type antibodies were detected in some moment of the follow up. Three of these corresponded to seroconversion. Cytomegalovirus was detected in urine in 41 percent of patients and it was not detected in lymphocytes. Shell vial assay detected the virus in 5 of 13 urine samples and in 1 of 7 lymphocyte samples. Polymerase chain reaction was positive in 12 of the 29 patients. In six patients, an acute rejection was postulated and there was no relation of rejection episodes with viral detection. In two patients, a disease caused by cytomegalovirus was postulated. One of these patients had a seroconversion during follow up. Conclusions: The prevalence of positive serum indices of cytomegalovirus infection was similar to that reported in the general population. However, the frequency of reactivation and viral disease was lower than that reported elsewhere. The techniques used in this study can be useful to confirm the suspicion of cytomegalovirus disease. However they do not predict the occurrence or evolution of the disease caused by the virus nor viral reactivation in renal transplant recipients

Tratamiento con ganciclovir en neumonía intersticial por citomegalovirus / Treatment with ganciclovir of cytomegalovirus insterstitial pneumonia

La neumonía es una de las manifestaciones más frecuentes de infección por citomegalovirus en pacientes inmunosuprimidos, con letalidad cercana a 100% hasta el uso de ganciclovir. Se describe el caso de un preescolar con linfoma no Hodgkin que ingresó a una unidad de tratamiento intensivo a causa de choque séptico a Haemophilus influenzae, serotipo b, no productor de ß lactamasa, secundario a aplasia medular por quimioterapia. Evolucionó con neumonía intersticial, que obligó a mantenerlo conectado a un ventilador mecánico, con resultados negativos en los cultivos bacteriológicos para aerobios, anaerobios y hongos, por lo que se usaron infructuosamente diversos esquemas antibióticos como prueba terapéutica. Como no mejoró su función respiratoria, se realizó biopsia pulmonar a cielo abierto, encontrándose alteraciones sugerentes de neumonía intersticial por citomegalocirus. Los cultivos para el virus fueron negativos, pero la inmunofluorescencia IgG mostró un título de 1:128, si bien la de IgM era negativa. Se hizo tratamiento con ganciclovir sódico 10 mg por kg por día, en coincidencia con lo cual el paciente inició un curso favorable, siendo posible desconectarle del ventilador mecánico algunos días más tarde. Dos meses después había mejorado clínica y radiológicamente. No se registraron efectos adversos renales, hepáticos y hematológicos del tratamiento

Tratamento da retinite por citomegalovirus em paciente portador da S.I.D.A / Treatment of citomegalovirus retinitis in A.I.D.S

Os autores descrevem dois casos de retinite por citomegalovirus em pacientes portadores de Síndrome de Imunodeficiência Adquirida, diagnosticados oftalmoscopicamente e confirmados por angiofluoresceinografia. Citam principais características biológicas desta retinite. Säo tratados efetivamente com ganciclovir, um de forma sistêmica e outro de forma local, intra-vítrea. Discorrem acerca de sua posologia, evidenciando os benefícios, riscos e efeitos secundários de cada uma das vias de administraçäo. Relatam os parâmetros oculares que devem ser pesquisados para o seu correto acompanhamento e a necessidade da documentaçäo retino e angiofluoresceinográfica

Consideraçöes sobre retinite a citomegalovírus e síndrome de necrose retiniana aguda / Considerations about citomegalovirus retinitis and acute retinal necrosis

Os autores fazem uma revisäo bibliográfica na literatura dos últimos 10 anos, sobre retinite a Citomegalovírus e Necrose Retiniana Aguda, apresentando 2 casos clínicos e discutindo sobre a eficácia dos tratamentos empregados na atualidade