RESUMO
BACKGROUND AND AIMS: Hepatitis C virus (HCV)-viremic organs are underutilized, and there is limited real-world experience on the transplantation of HCV-viremic solid organs into recipients who are HCV negative. APPROACH AND RESULTS: Patients listed or being evaluated for solid organ transplant after January 26, 2018, were educated and consented by protocol on the transplantation of HCV-viremic organs. All recipients were HCV nucleic acid test and anti-HCV antibody negative at the time of transplant and received an HCV-viremic organ. The primary outcome was sustained virological response (SVR) at 12 weeks after completion of direct-acting antiviral (DAA) therapy (SVR12 ). Seventy-seven patients who were HCV negative underwent solid organ transplantation from a donor who was HCV viremic. No patients had evidence of advanced hepatic fibrosis. Treatment regimen and duration were at the discretion of the hepatologist. Sixty-four patients underwent kidney transplant (KT), and 58 KT recipients had either started or completed DAA therapy. Forty-one achieved SVR12 , 10 had undetectable viral loads but are not eligible for SVR12 , and 7 remain on treatment. One KT recipient was a nonresponder because of nonstructural protein 5A resistance. Four patients underwent liver transplant and 2 underwent liver-kidney transplant. Three patients achieved SVR12 , 1 has completed DAA therapy, and 2 remain on treatment. Six patients underwent heart transplant and 1 underwent heart-kidney transplant. Six patients achieved SVR12 and 1 patient remains on treatment. CONCLUSIONS: Limited data exist on the transplantation of HCV-viremic organs into recipients who are HCV negative. Our study is the largest to describe a real-world experience of the transplantation of HCV-viremic organs into recipients who are aviremic. In carefully selected patients, the use of HCV-viremic grafts in the DAA era appears to be efficacious and well tolerated.
Assuntos
Antivirais/uso terapêutico , DNA Viral/análise , Transplante de Coração , Hepacivirus/genética , Hepatite C/prevenção & controle , Transplante de Rim , Transplante de Fígado , Complicações Pós-Operatórias/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Aloenxertos , Feminino , Hepatite C/transmissão , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Amplificação de Ácido Nucleico , Complicações Pós-Operatórias/virologia , Resposta Viral Sustentada , Doadores de Tecidos , Viremia/virologiaRESUMO
Polyomavirus nephropathy (PVN) is a major complication of kidney transplantation. Most reports describe polyomavirus viremia either precedes or is detectable at the time of diagnosis of PVN. This association is the basis of current screening recommendations. We retrospectively reviewed the PCR results of blood and urine samples from 29 kidney transplant recipients with biopsy-proven PVN. Biopsies were performed for a rise in serum creatinine or persistent high-level BK viruria. All biopsies showed polyoma virus large T-antigen expression in tubular epithelium using immunohistochemistry. All had viruria preceding or at the time of biopsy (range, 5.2 × 104 to >25 × 106 BKV DNA copies/ml). Twenty (69%) had viremia ranging from 2.5 × 103 to 4.3 × 106 copies/ml at the time of the biopsy. Via blood BK PCR assay, nine (31%) had no BK viremia detected either preceding or at the time of the biopsy. In five recipients where sufficient specimen permitted, additional plasma BK assessment revealed positive detection of viremia. A comparative analysis of assays from two centres was performed with spiked samples. BK DNA may not be detected in the blood of some kidney transplant recipients with histologically confirmed PVN. This may reflect limitation of whole blood as opposed to plasma-based BK DNA assessment.
Assuntos
Vírus BK , DNA Viral/sangue , Nefropatias/diagnóstico , Transplante de Rim/efeitos adversos , Infecções por Polyomavirus/diagnóstico , Infecções Tumorais por Vírus/diagnóstico , Viremia/diagnóstico , Antígenos Transformantes de Poliomavirus/metabolismo , DNA Viral/genética , Feminino , Humanos , Imuno-Histoquímica , Rim/virologia , Nefropatias/etiologia , Nefropatias/virologia , Masculino , Pessoa de Meia-Idade , Plasma/virologia , Reação em Cadeia da Polimerase , Infecções por Polyomavirus/etiologia , Infecções por Polyomavirus/virologia , Estudos Retrospectivos , Infecções Tumorais por Vírus/etiologia , Infecções Tumorais por Vírus/virologia , Viremia/etiologia , Viremia/virologiaRESUMO
AIMS: Treatment strategies for breast cancer continue to evolve. No uniformity exists in the UK for the management of node-positive breast cancer patients. Most centres continue to use conventional histopathology of sampled sentinel lymph nodes (SLNs), which requires delayed axillary clearance in up to 25% of patients. Some use touch imprint cytology or frozen section for intraoperative testing, although both have inherent sensitivity issues. An intraoperative molecular diagnostic approach helps to overcome some of these limitations. The aim of this study was to assess the clinical effectiveness of Metasin, a molecular method for the intraoperative evaluation of SLNs. METHODS AND RESULTS: RNA from 3296 lymph nodes from 1836 patients undergoing SLN assessment was analysed with Metasin. Alternate slices of tissue were examined in parallel by histology. Cases deemed to be discordant were analysed by protein gel electrophoresis. There was concordance between Metasin and histology in 94.1% of cases, with a sensitivity of 92% [95% confidence interval (CI) 88-94%] and a specificity of 97% (95% CI 95-97%). Positive and negative predictive values were 88% and 98%, respectively. Over half of the discordant cases (4.4%) were ascribed to tissue allocation bias (TAB). CONCLUSIONS: Clinical validation of the Metasin assay suggests that it is sufficiently sensitive and specific to make it fit for purpose in the intraoperative setting.
Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/patologia , Metástase Linfática/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos , Linfonodo Sentinela/patologia , Feminino , Humanos , Período Intraoperatório , Biópsia de Linfonodo Sentinela/métodosRESUMO
BACKGROUND: In the last 10 years, severe obesity and the associated metabolic syndrome have reached pandemic proportions and consequently have significantly increased the prevalence of related co-morbidities such as chronic kidney disease (CKD). One in 7 people in the United States have CKD, and 90% of those are not aware of it. OBJECTIVES: Following sleeve gastrectomy (SG) in patients with severe obesity and baseline CKD stage ≥2, to determine improvement of glomerular function and analyze the relationship between kidney function and weight loss. SETTING: US Hospital, Academic Institution. METHODS: We retrospectively reviewed the charts of all patients who underwent SG at our institution from 2010 to 2019. Kidney function assessment using the Chronic Kidney Disease Epidemiology Collaboration Study (CKD-EPI) equation and classification was carried out preoperatively and postoperatively at 12-months follow-up. Propensity score matching (1:1 ratio) was used to balance the distribution of covariates between patients with a baseline estimated glomerular filtration rate (eGFR) <90 mL/min/1.73 m2 and patients with normal kidney function. RESULTS: We calculated the eGFR of 1330 bariatric patients who underwent SG. Of these patients, 18.79% (n = 250) met the criteria for CKD-EPI eGFR calculation preoperatively and at 12-months follow-up after SG. From the 250 patients included in the analysis, 42% (n = 105) were classified as CKD stage ≥2. When comparing the baseline preoperative eGFR at 12-months follow-up after SG, we observed an improvement of 8.26 ± 11.89 mL/min/1.73 m2 in CKD stage ≥2 (eGFR <90 mL/min/1.73 m2) as compared with 1.98 ± 10.25 mL/min/1.73 m2 in patients with eGFR >90 mL/min/1.73 m2 (P < .001). CONCLUSION: There is short-term improvement of the eGFR in patients with severe obesity following SG. This improvement is significant in CKD stages ≥2 and seems unrelated to weight loss.
Assuntos
Cirurgia Bariátrica , Obesidade Mórbida , Insuficiência Renal Crônica , Gastrectomia , Taxa de Filtração Glomerular , Humanos , Rim , Obesidade Mórbida/complicações , Obesidade Mórbida/cirurgia , Pontuação de Propensão , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/cirurgia , Estudos Retrospectivos , Redução de PesoRESUMO
BACKGROUND: We examined the link between increased intra-abdominal pressure, intracranial pressure, and vasopressin release as a potential mechanism. Intra-abdominal pressure, produced by abdominal-cavity insufflation with carbon dioxide (CO2) during laparoscopic abdominal procedures to facilitate visualization, is associated with various complications, including arterial hypertension and oliguria. METHODS: Mean arterial pressure, optic nerve sheath diameter, measured as a proxy for intracranial pressure, plasma vasopressin, serum and urine osmolarity, and urine output were measured 4 times during laparoscopic sleeve gastrectomy in 42 patients: before insufflation with CO2 (T0); after insufflation to 15 cm water (H2O) pressure, with 5 cm H2O positive end-expiratory pressure (T1); after positive end-expiratory pressure was raised to 10 cm H2O (T2); and after a return to the baseline state (T3). Mean values at T0 to T3 and the directional consistency of changes (increase/decrease/ unchanged) were compared among the 4 data-collection points. RESULTS: Statistically significant elevations (all P ≤ .001) were noted from T0 to T1 and from T0 to T2 in mean arterial pressure, optic nerve sheath diameter, and vasopressin, followed by decreases at T3. For optic nerve sheath diameter and vasopressin, the increases at T1 and T2 occurred in 98% and 100% of patients, ultimately exceeding normal levels in 88 and 97%, respectively. Conversely, urine output fell from T0 to T1 and T2 by 60.9 and 73.4%, decreasing in 88.1% of patients (all P < .001). Patients with class II obesity exhibited statistically greater increases in optic nerve sheath diameter and vasopressin, but statistically less impact on urine output, than patients with class III obesity. CONCLUSION: Increased mean arterial pressure, intracranial pressure, and vasopressin release appear to be intermediary steps between increased intra-abdominal pressure and oliguria. Further research is necessary to determine any causative links between these physiological changes.
Assuntos
Hipertensão Intra-Abdominal/fisiopatologia , Hipertensão Intracraniana/fisiopatologia , Oligúria/fisiopatologia , Pneumoperitônio Artificial/efeitos adversos , Vasopressinas/metabolismo , Adulto , Idoso , Feminino , Gastrectomia/efeitos adversos , Gastrectomia/métodos , Humanos , Hipertensão Intra-Abdominal/epidemiologia , Hipertensão Intra-Abdominal/etiologia , Hipertensão Intracraniana/epidemiologia , Hipertensão Intracraniana/etiologia , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Masculino , Pessoa de Meia-Idade , Oligúria/epidemiologia , Oligúria/etiologia , Estudos Prospectivos , Sistema Vasomotor/fisiopatologia , Adulto JovemRESUMO
There is an association between inflammation and hemostatic changes that can result in a hypercoagulable state. We report a 34-year-old male who presented with a second episode of deep vein thrombosis. Tuberculosis was diagnosed while looking for secondary causes. The patient was treated with rifampicin, isoniazid, pyrazinamide and ethambutol along with low-molecular-weight heparin and warfarin. Tuberculosis has several mechanisms that induce a hypercoagulable state and can lead to thromboembolic complications.
Assuntos
Inflamação/complicações , Tuberculose Pulmonar/complicações , Trombose Venosa/complicações , Adulto , Humanos , Masculino , RecidivaRESUMO
Two children with suspected ITP are described. One child was treated outside with corticosteroids and was diagnosed acute lymphoblastic leukemia. Another child was fresh and diagnosed as acute myeloid leukemia on bone marrow aspirate examination. Both the children had no physical or peripheral smear finding suggestive of leukemia. We suggest that a bone marrow examination is required in developing countries for evaluation of thrombocytopenia before labeling it an immune thrombocytopenic purpura.
Assuntos
Exame de Medula Óssea , Leucemia Mieloide/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Púrpura Trombocitopênica Idiopática/diagnóstico , Doença Aguda , Corticosteroides/uso terapêutico , Criança , Diagnóstico Diferencial , Feminino , Humanos , Leucemia Mieloide/tratamento farmacológico , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológicoRESUMO
The clinical and hematological profile and treatment outcome of children with warm autoimmune hemolytic anemia (AIHA) were assessed using retrospective case record analysis. There were 26 (17 idiopathic; 9 secondary) patients with a median age of 11 years. Pallor (100%), fever (39%), and jaundice (59%) were the main presenting complaints. Jaundice was much more common in idiopathic (70%) compared to secondary (44%). Direct antiglobulin test was negative in 3 patients. Oral prednisolone produced remission in 81% patients. Four patients relapsed after a median period of 7 months (2 months to 2 year) after response. All responded to a second course of steroids in median 14 days. One child required cyclosporin A in addition. No correlation was found between response and parameters such as age, sex, jaundice, low pretreatment hemoglobin, reticulocyte count, total leukocyte count, platelet count, subtype of AIHA, and hepatosplenomegaly. Relapse correlated with increased duration between the onset of symptoms and treatment. This study indicates that oral prednisolone is an effective therapy for autoimmune hemolytic anemia. In refractory cases cyclosporine A may be useful.
Assuntos
Anemia Hemolítica Autoimune/tratamento farmacológico , Anemia Hemolítica Autoimune/patologia , Adolescente , Criança , Pré-Escolar , Feminino , Febre , Humanos , Lactente , Icterícia , Masculino , Palidez , Prednisolona/uso terapêutico , Recidiva , Indução de Remissão , Estudos RetrospectivosRESUMO
Lupus nephritis is one of the more serious manifestations of the systemic autoimmune disease, systemic lupus erythematosus, and is associated with considerable morbidity and even mortality. Treatment remains problematic, particularly in terms of controlling the underlying disease process while at the same time preventing unacceptable side effects of therapy. In recent years, clinical trials have started to define optimum regimens of the immunosuppressive agents presently in use. The etiology and pathogenesis of systemic lupus erythematosus and lupus nephritis still are understood incompletely. Nevertheless, insights gained from basic science research in both animals and human beings now are being translated into newer therapies that have the potential to be safer and more specific than those currently available.
Assuntos
Nefrite Lúpica , Autoimunidade/imunologia , Humanos , Imunossupressores/uso terapêutico , Nefrite Lúpica/tratamento farmacológico , Nefrite Lúpica/imunologia , Nefrite Lúpica/patologia , PrognósticoRESUMO
Intestinal protozoal infections are common in our country because of poor hygiene and tropical conditions. The efficacy of trichrome staining to screen stool smear was compared with commonly used methods i.e. concentrated iodine mount and direct wet mount to test its better effectiveness. All Stool samples were first examined by routine methods i.e. direct wet mount and iodine staining. A portion of stool sample was also inoculated in vial containing polyvinyl alcohol (PVA) fixative. From PVA preserved samples, slides were prepared and stained by modified wheately's trichrome method. The results of both methods were compared and relative accuracy was calculated. 1054 stool specimens were examined and 259 parasites detected, of which 20.7% were protozoa and 3.7% helminthde. Trichrome staining detected 19.1% protozoa while routine methods detected 12.9% protozoa. For identification of protozoa, accuracy was 91.8% in favor trichrome staining and 61.8% by wet mount and iodine staining. Trichrome stained smear alone can be used as screening method in those geographic areas where protozoa infections are common.
Assuntos
Compostos Azo , Amarelo de Eosina-(YS) , Eucariotos/isolamento & purificação , Verde de Metila , Infecções por Protozoários/diagnóstico , Animais , Eucariotos/classificação , Fezes/parasitologia , Helmintos , Humanos , Coloração e RotulagemRESUMO
A 2-year-old boy presented with fever, recurrent infections and multiple skin lesions. He had anemia, eczematous skin lesions, cervical lymph node enlargement, hepatomegaly and lytic lesions on skull x-ray. The skin infiltrates were CD 68, CD 1a positive and S100 positive. He was diagnosed as disseminated langerhans cell histiocytosis. The occurrence of histiocytosis is reviewed and possible treatment is discussed.
Assuntos
Histiocitose de Células de Langerhans/diagnóstico , Antígenos CD/metabolismo , Antígenos CD1/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Pré-Escolar , Histiocitose de Células de Langerhans/imunologia , Histiocitose de Células de Langerhans/terapia , Humanos , Imuno-Histoquímica , Masculino , Proteínas S100/metabolismoAssuntos
Antineoplásicos/uso terapêutico , Febre , Hospitais , Leucemia Mieloide Aguda/tratamento farmacológico , Neutrófilos/citologia , Alta do Paciente/estatística & dados numéricos , Adolescente , Adulto , Criança , Feminino , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Indução de Remissão , Resultado do TratamentoAssuntos
Arsenicais/efeitos adversos , Arsenicais/uso terapêutico , Artrite Reumatoide/induzido quimicamente , Artrite Reumatoide/patologia , Leucemia Promielocítica Aguda/tratamento farmacológico , Leucemia Promielocítica Aguda/patologia , Óxidos/efeitos adversos , Óxidos/uso terapêutico , Idoso , Trióxido de Arsênio , Artrite Reumatoide/complicações , Quimioterapia Combinada , Humanos , Leucemia Promielocítica Aguda/complicações , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/metabolismo , MasculinoAssuntos
Glomerulonefrite/diagnóstico , Nefrite Lúpica/diagnóstico , Creatinina/sangue , Evolução Fatal , Feminino , Glomerulonefrite/complicações , Glomerulonefrite/patologia , Hematúria/etiologia , Humanos , Glomérulos Renais/patologia , Glomérulos Renais/ultraestrutura , Nefrite Lúpica/complicações , Nefrite Lúpica/tratamento farmacológico , Nefrite Lúpica/patologia , Pessoa de Meia-Idade , Proteinúria/etiologiaRESUMO
A 4-yr-old boy developed autoimmune hemolytic anemia after rubella infection and clinical manifestations cleared up after decrease in rubella specific IgM titer without any specific therapy.
Assuntos
Anemia Hemolítica/etiologia , Rubéola (Sarampo Alemão)/complicações , Pré-Escolar , Teste de Coombs , Ensaio de Imunoadsorção Enzimática , Hemólise , Humanos , Masculino , Rubéola (Sarampo Alemão)/diagnósticoRESUMO
Dendritic cell (DC) activation by nucleic acid-containing IgG complexes is implicated in systemic lupus erythematosus (SLE) pathogenesis. However, it has been difficult to definitively examine the receptors and signaling pathways by which this activation is mediated. Because mouse FcgammaRs recognize human IgG, we hypothesized that IgG from lupus patients might stimulate mouse DCs, thereby facilitating this analysis. In this study, we show that sera and purified IgG from lupus patients activate mouse DCs to produce IFN-alpha, IFN-beta, and IL-6 and up-regulate costimulatory molecules in a FcgammaR-dependent manner. This activation is only seen in sera with reactivity against ribonucleoproteins and is completely dependent on TLR7 and the presence of RNA. As anticipated, IFN regulatory factor (IRF)7 is required for IFN-alpha and IFN-beta production. Unexpectedly, however, IRF5 plays a critical role in IFN-alpha and IFN-beta production induced not only by RNA-containing immune complexes but also by conventional TLR7 and TLR9 ligands. Moreover, DC production of IL-6 induced by these stimuli is dependent on a functional type I IFNR, indicating the need for a type I IFN-dependent feedback loop in the production of inflammatory cytokines. This system may also prove useful for the study of receptors and signaling pathways used by immune complexes in other human diseases.
Assuntos
Complexo Antígeno-Anticorpo/fisiologia , Células Dendríticas/imunologia , Imunoglobulina G/fisiologia , Fator Regulador 7 de Interferon/fisiologia , Fatores Reguladores de Interferon/fisiologia , Interferon Tipo I/biossíntese , Interleucina-6/biossíntese , RNA/imunologia , Animais , Células Cultivadas , Células Dendríticas/metabolismo , Humanos , Fator Regulador 7 de Interferon/deficiência , Fator Regulador 7 de Interferon/genética , Fatores Reguladores de Interferon/deficiência , Fatores Reguladores de Interferon/genética , Ligantes , Lúpus Eritematoso Sistêmico/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor 7 Toll-Like/metabolismo , Receptor 7 Toll-Like/fisiologia , Receptor Toll-Like 9/metabolismo , Receptor Toll-Like 9/fisiologiaRESUMO
Chronic lymphocytic leukemia (CLL) is the most common form of leukemia in elderly people. The clinico-hematological profile and treatment outcome of patients with CLL were assessed using retrospective case record analysis over 11 years. There were 95 (75 males: 20 females) patients with a median age of 61 years. Thirty patients were aged 55 years or less (young CLL patients) and 65 were more than 55 years of age (elder CLL patients). Sixty percent patients had non-specific complaints, such as weakness, cough and indigestion. Twenty-six (27%) patients had pallor and 24 (25%) had fever as initial presenting manifestation. Bleeding manifestations were seen in 7 patients. Seven patients were diagnosed incidentally. Lymphadenopathy, splenomegaly and hepatomegaly were seen in 52 (55%), 63 (66%) and 60 (63%) patients, respectively. The median white blood cell count and absolute lymphocyte counts were 70,600 and 51,490/mul, respectively. Three patients had autoimmune hemolytic anemia. Twenty-five patients (26%) had anemia with hemoglobin < 11 g/dl and thrombocytopenia with platelet count 100 x 10(3)/mm(3) was seen in 17 (18%). Interstitial nodular, mixed and diffuse bone marrow (BM) involvement was seen in 10.2, 67.3, 6.1 and 16.3% cases, respectively. Eighteen (60%) young patients and 35 (54%) older patients required treatment with chlorambucil. The mean time from initial diagnosis to treatment was 4.6 +/- 10.7 months. None of our patient attained complete response. Six patients obtained partial response. Median duration of chlorambucil was 7 months (1-86 months). Forty-six patients had stable disease. Three patients died. Median survival of study group was 4 years (8 months-13 years). In older CLL it was 4 years (8 months-11 years) and in young patients, survival duration was 5.5 years (1-13 years).
Assuntos
Leucemia Linfocítica Crônica de Células B/diagnóstico , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anemia , Clorambucila/uso terapêutico , Feminino , Testes Hematológicos , Hepatomegalia , Humanos , Índia , Leucemia Linfocítica Crônica de Células B/complicações , Leucemia Linfocítica Crônica de Células B/epidemiologia , Leucemia Linfocítica Crônica de Células B/mortalidade , Doenças Linfáticas , Masculino , Pessoa de Meia-Idade , Esplenomegalia , Análise de Sobrevida , TrombocitopeniaRESUMO
The clinico-hematological profile and treatment outcome of patients with autoimmune hemolytic anemia (AIHA) were assessed using a retrospective case record analysis. There were 79 (52 primary; 27 secondary) consecutive patients identified with a median age of 30.5 years. The main presenting complaints were pallor (94%), fever (46%), jaundice (51%), bleeding manifestations (10%) and splenomegaly (68%). Jaundice was much more common in primary (63%) as opposed to secondary (26%) disease. The direct antiglobulin test was negative in six patients. Oral prednisolone produced remission in 87.5% patients. Six patients (three children, three adults) relapsed after a median period of 2 months after response. All of these responded to a second course of steroids, in a median period of 14 days. No correlation was found between response and the parameters of age, sex, jaundice, low pretreatment hemoglobin, reticulocyte count, total leucocyte count (TLC), platelet count, subtype of AIHA and hepatosplenomegaly. Relapse correlated with increased duration between the onset of symptoms and treatment (r = 0.996; p = 0.0001).
Assuntos
Anemia Hemolítica Autoimune/tratamento farmacológico , Anti-Inflamatórios/administração & dosagem , Prednisolona/administração & dosagem , Administração Oral , Adolescente , Adulto , Idoso , Anemia Hemolítica Autoimune/sangue , Anemia Hemolítica Autoimune/complicações , Criança , Pré-Escolar , Feminino , Humanos , Índia , Lactente , Icterícia/sangue , Icterícia/dietoterapia , Icterícia/etiologia , Masculino , Pessoa de Meia-Idade , Recidiva , Indução de Remissão , Estudos Retrospectivos , Fatores de TempoRESUMO
Cytochemistry and immunophenotyping are established methods in the diagnosis of most leukemias but the role of electron microscopy in diagnosis, apart from understanding the cellular morphology is less studied. We present here 50 cases of acute leukemias that were studied for morphology, conventional cytochemistry, immunophenotyping and transmission electron microscopy (TEM), including ultrastructural cytochemistry using myeloperoxidase (MPO) and platelet peroxidase activity. TEM morphology using ultrastructural cytochemistry helped in definitive typing in one mixed lineage leukemia case, one AML-M5b, one AML-M6b and one microgranular variant of APML. Thus, ultrastructural studies may be useful in accurate diagnosis of biphenotypic leukemia and further classification of acute leukemias. Also, in cases with hypercellular marrow and with associated myelofibrosis, where the marrow aspirate gives low cell count, ultrastructural studies are a valuable aid to arriving at an accurate diagnosis.