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BACKGROUND: Infants younger than 6 months of age are not eligible for coronavirus disease 2019 (COVID-19) vaccinations. Maternal variables during pregnancy and the postnatal period may affect the clinical and laboratory course of COVID-19 positive infants. OBJECTIVES: To assess the clinical manifestation and laboratory differences in infants with three maternal variables: breastfeeding, vaccinated, and co-illness. METHODS: We conducted a single-center retrospective cohort study of positive COVID-19 infants with three subgroups of maternal variables. The population included infants under 6 months of age hospitalized due to COVID-19. Data about clinical features, laboratory tests, and maternal information including vaccination status, breastfeeding status and maternal positive COVID-19 infection was gathered. All variables were compared among the three subgroups. RESULTS: Breastfed infants had shorter hospitalization period (mean 2.61 ± 1.378 days) compared to non-breastfed infants (mean 3.8 ± 1.549) (P = 0.051). COVID-19 infants of positive COVID-19 mothers had a higher absolute neutrophil count (mean 4.4 ± 3.8) compared to infants of COVID-19 negative mothers (mean 2.7 ± 2.4) (P = 0.042). CONCLUSIONS: Breastfeeding was associated with shorter periods of hospitalization in COVID-19 positive infants. In addition, positive COVID-19 infants of mothers who were positive for COVID-19 are likely to have a higher absolute neutrophils count.
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COVID-19 , Feminino , Gravidez , Humanos , Lactente , COVID-19/epidemiologia , Estudos Retrospectivos , Hospitalização , Contagem de Leucócitos , MãesRESUMO
BACKGROUND: Factor VII (FVII) deficiency is characterized by normal activated partial thromboplastin time (aPTT) and prolonged prothrombin time (PT) values. It is diagnosed by determining protein level and coagulation activity (FVII:C). FVII:C measurements are expensive and time consuming. OBJECTIVES: To analyze correlations between PT, international normalized ratio (INR), and FVII:C in pediatric patients before otolaryngology surgery and to establish alternative methods for identifying FVII deficiency. METHODS: FVII:C data were collected from 96 patients with normal aPTT and prolonged PT values during preoperative otolaryngology surgery coagulation workup between 2016 and 2020. We compared demographic and clinical parameters using Spearman correlation coefficient and receiver operating characteristic (ROC) curve analysis to determine the accuracy of PT and INR values to predict FVII deficiency. RESULTS: The median values of PT, INR and FVII:C were 13.5 seconds, 1.14, and 67.5%, respectively. In total, 65 participants (67.7%) displayed normal FVII:C compared to 31 (32.3%) with decreased FVII:C. A statistically significant negative correlation was observed between FVII:C and PT values and between FVII:C and INR. Despite statistically significant ROC of 0.653 for PT (P-value = 0.017, 95% confidence interval [95%CI] 0.529-0.776) and 0.669 for INR (P-value = 0.08, 95%CI 0.551-0.788), we were unable to determine an optimal cutoff point to predict FVII:C deficiency with high sensitivity and high specificity. CONCLUSIONS: We could not identify a PT or INR threshold to best predict clinically relevant FVII:C levels. When PT is abnormal, determining FVII:C protein levels is needed for diagnosing FVII deficiency and considering surgical prophylactic treatment.
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Deficiência do Fator VII , Fator VII , Humanos , Criança , Tempo de Protrombina , Coeficiente Internacional Normatizado , Testes de Coagulação Sanguínea , Deficiência do Fator VII/diagnósticoRESUMO
Description of three cases of 4-7-year-old male children presenting with a seizure without a prior history of epilepsy, 2-4 weeks after recovering from COVID-19. All three children were admitted to the pediatric department at Laniado Hospital in Netanya, Israel, and presented with seizures without fever. We found common characteristics among the children that can imply a predisposition for neurological complications of Covid-19.
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AIM: Temporal changes in common pathogens that cause clinical dysentery have been described in Europe. We aimed to describe the distribution of pathogens and their antibiotic resistance in hospitalised Israeli children. METHODS: This study retrospectively studied children hospitalised for clinical dysentery, with or without a positive stool culture, from 1 January 2016 to 31 December 2019. RESULTS: We diagnosed 137 patients (65% males), with clinical dysentery at a median age of 3.7 (interquartile range 1.5-8.2) years. Stools were cultured in 135 patients (99%), and the results were positive in 101 (76%). These comprised Campylobacter (44%), Shigella sonnei (27%), non-typhoid Salmonella (18%) and enteropathogenic Escherichia coli (12%). Only one of the 44 Campylobacter cultures was resistant to erythromycin and one of the 12 enteropathogenic Escherichia coli cultures was resistant to ceftriaxone. None of the Salmonella and Shigella cultures were resistant to ceftriaxone or erythromycin. We did not find any pathogens that were associated with a typical clinical presentation or laboratory results on admission. CONCLUSION: The most common pathogen was Campylobacter, in line with recent European trends. Bacterial resistance for commonly prescribed antibiotics was rare, and these findings support the current European recommendations.
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Infecções Bacterianas , Campylobacter , Disenteria , Shigella , Masculino , Humanos , Criança , Lactente , Pré-Escolar , Feminino , Antibacterianos/uso terapêutico , Estudos Retrospectivos , Ceftriaxona/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Salmonella , Eritromicina/farmacologia , Eritromicina/uso terapêutico , Diarreia , Fezes/microbiologia , Farmacorresistência BacterianaRESUMO
INTRODUCTION: Malaria is an infectious disease caused by the Plasmodium protozoa and transmitted by the female Anopheles mosquitos. Delayed diagnosis or treatment could evolve to life threatening complications and mortality that typically occur in children or travelers to endemic areas. In this article, we describe a case of a 6 year old healthy child, who travelled with his family to an endemic area in Ethiopia. A week prior to his hospitalization, the patient developed intermittent fever. The disease, its' risk factors and characteristics are described throughout this article.
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Malária , Plasmodium , Animais , Humanos , Feminino , Criança , Etiópia , Vigilância da População , Malária/diagnóstico , Malária/epidemiologia , ViagemRESUMO
Background: Trachyonychia is a benign nail condition, most commonly seen in children. Trachyonychia manifests as excessive longitudinal ridging, nail roughness, and nail brittleness. Treatment is sought mainly for esthetic reasons as well as functional reasons. A number of therapeutic approaches exist, mainly based on case reports or small non-comparative case series. Aims: To report treatment outcome among patients with trachyonychia. Methods: A retrospective case-series study was conducted among patients who were treated trachyonychia between years 2017 and 2020. Patients were prescribed fluocinonide 0.05% with bifonazole 1% cream, applied with or without occlusion, and methylprednisolone 1-2 mg/nail, injected into the involved nail matrix, or oral cyclosporine 3 mg/kg. Complete response (over 90% improvement) and partial response (over 50% improvement) were assessed. Results: A total of 43 patients with trachyonychia were included [mean age 10.0 years (±5.7), 69.8% males, mean disease duration 4.7 years (±3.0)]. In 90.7% of the cases, topical fluocinonide\bifonazole cream was prescribed. Under-occlusion topical application was found to be highly effective, achieving complete response in 35.3% and partial response in an additional 52.9% of the patients. Occluded application was also found to be significantly more effective than non-occluded application. Treatment efficacy was not affected by the severity of nail roughness, trachyonychia morphology, or whether trachyonychia was idiopathic or coexisted with other dermatological conditions. Conclusion: Occluded application of fluocinonide plus bifonazole cream is efficient for the treatment of trachyonychia and should be considered a first line of treatment.
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Promoting SARS-CoV-2 vaccination has been a global mission since the first vaccines were approved for emergency use. Alongside the excitement following the possibility of eradicating SARS-CoV-2 and ending the COVID-19 pandemic, there has been ample vaccine hesitancy, some due to the abundant reporting of adverse reactions. We report here that the occurrence of BNT162b2 vaccine adverse reactions is associated with enhanced antibody response. We found a statistically significant correlation between having an adverse reaction, whether local or systemic, and higher antibody levels. No sex difference was observed in antibody levels. However, as was recently reported, the antibody response was found to be lower among older vaccinees. The demonstration of a clear correlation between adverse reactions and antibody levels may help reduce vaccination hesitancy by reassuring that the presence of such reactions is an indication of a well-functioning immune system.
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Rosacea is a common inflammatory facial skin condition affecting the adult population. Its papulopustular subtype is mainly treated pharmacologically by topical and oral antibiotics. For severe or antibiotics-recalcitrant disease, daily low-dose isotretinoin has also been reported to be effective. However, no previous study has assessed the efficacy of once-weekly administered isotretinoin for papulopustular rosacea. For this purpose, a retrospective comparative study was conducted. For severe rosacea, 40 mg/week isotretinoin (24 patients) was administered. For mild to moderate rosacea, once-weekly 20 mg/week isotretinoin (28 patients) was compared with 100 mg/day minocycline (24 patients). Treatment courses lasted 4 to 7 months. Forty milligrams per week isotretinoin was highly effective for severe rosacea, achieving complete response (over 90% improvement) in 62.5% of patients and partial response (50%-90% improvement) in additional 29.2% of patients. Twenty milligrams per week isotretinoin and hundred milligrams per day minocycline showed comparable efficacy for mild to moderate rosacea (complete response of 10.7% vs 8.3% and partial response of 28.6% vs 33.3%, respectively). This study demonstrates that that the use of a weekly low-dose isotretinoin is an effective treatment for papulopustular rosacea, including among patients with severe disease.
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Fármacos Dermatológicos , Rosácea , Adulto , Antibacterianos , Humanos , Isotretinoína , Minociclina , Estudos Retrospectivos , Rosácea/diagnóstico , Rosácea/tratamento farmacológicoRESUMO
BACKGROUND AND OBJECTIVES: Coronavirus disease 2019 (COVID-19) is associated with higher morbidity and mortality in patients on maintenance hemodialysis. Patients on dialysis tend to have a reduced immune response to infection or vaccination. We aimed to assess, for the first time to the best of our knowledge, the humoral response following vaccination with the BNT162b2 vaccine in patients on maintenance hemodialysis and the factors associated with it. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: The study included 56 patients on maintenance hemodialysis (dialysis group) and a control group composed of 95 health care workers. All participants had received two doses of the BNT162b2 (Pfizer-BioNTech) vaccine. The serology testing was done using Quant II IgG anti-Spike severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) assay by Abbott a median of 30 days after receipt of the second dose of the vaccine. RESULTS: All subjects in the control group developed an antibody response compared with 96% (54 of 56) positive responders in the dialysis group. The IgG levels in the dialysis group (median, 2900; interquartile range, 1128-5651) were significantly lower than in the control group (median, 7401; interquartile range, 3687-15,471). A Mann-Whitney U test indicated that this difference was statistically significant (U=1238; P<0.001). There was a significant inverse correlation of age and IgG levels in both groups. The odds of being in the lower quartile were significantly higher for older individuals (odds ratio, 1.11 per year of age; 95% confidence interval, 1.08 to 1.20; P=0.004) and for the dialysis group compared with the control group (odds ratio, 2.7; 95% confidence interval, 1.13 to 7.51; P=0.05). Within the dialysis group, older age and lower lymphocyte count were associated with antibody response in the lower quartile (odds ratio, 1.22 per 1-year older; 95% confidence interval, 1.13 to 1.68; P=0.03 and odds ratio, 0.83 per 10-e3/µl-higher lymphocyte count; 95% confidence interval, 0.58 to 0.97; P=0.05). CONCLUSIONS: Although most patients on maintenance hemodialysis developed a substantial humoral response following the BNT162b2 vaccine, it was significantly lower than controls. Age was an important factor in the humoral response, regardless of chronic medical conditions.
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Anticorpos Antivirais/sangue , Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , Diálise Renal , Vacinação , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Vacina BNT162 , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , SARS-CoV-2/imunologiaRESUMO
BACKGROUND: In all, 15-30% of pediatric immune thrombocytopenia (ITP) patients will remain chronically thrombocytopenic at 1 year post diagnosis. All attempts to classify patients at diagnosis have proven unsuccessful. We hypothesized that a different pathophysiology is responsible for non-chronic versus chronic pediatric ITP. We aimed to examine differences in the apoptotic markers' presentation at diagnosis between non-chronic and chronic patients. METHODS: Blood samples were collected from 42 pediatric patients with newly diagnosed ITP prior to initiation of treatment. We incubated patients' sera with control platelets and compared the results among three research groups: healthy controls, chronic ITP, and non-chronic ITP patients. We measured apoptotic markers phosphatidylserine (PS) exposure and mitochondrial inner membrane potential (ΔΨm) by flow cytometry and the level of human apoptotic proteins by Human Apoptosis Array. RESULTS: We found increased platelet PS exposure and decreased ΔΨm in response to all ITP patients' sera compared to control subjects. Human Apoptotic Array revealed an increased expression of five apoptotic proteins: BIM, CD40, IGFBP2, P21, and SMAC, following sera incubation of non-chronic pediatric ITP patients, compared to chronic patients' sera, at diagnosis. CONCLUSIONS: Our data contribute to knowledge on apoptosis markers that may aid in predicting the prognosis of children with ITP. IMPACT: The key message of our article is that children with chronic ITP have a different apoptotic profile compared to non-chronic ITP. Addition to existing literature: This is the first study comparing apoptotic markers between children with chronic ITP to non-chronic ITP. IMPACT: Our findings indicate that, in the future, apoptotic markers may help to classify ITP patients into non-chronic versus chronic ones, at diagnosis.
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Apoptose , Púrpura Trombocitopênica Idiopática/patologia , Adolescente , Biomarcadores/sangue , Estudos de Casos e Controles , Criança , Pré-Escolar , Progressão da Doença , Feminino , Citometria de Fluxo , Humanos , Lactente , Masculino , Estudos Prospectivos , Púrpura Trombocitopênica Idiopática/sangueRESUMO
BACKGROUND: There is limited clinical information on coronavirus disease-19 (COVID-19) patients in Israel. OBJECTIVES: To describe the characteristics, outcomes, and potential associations of hospitalized COVID-19 patients in Israel. METHODS: We conducted a single-center, retrospective study of 58 consecutive laboratory-confirmed COVID-19 patients admitted to Laniado Hospital, Israel, between 14 March 2020 and 14 May 2020. Demographic, clinical, and laboratory data on admission were collected and analyzed, and the association to subsequent respiratory failure was assessed. RESULTS: Mean age of patients was 70.7 ± 16.9 years (53% males, 47% females.); 74% had at least one co-morbidity. Most patients were of Jewish Ashkenazi descent. During hospitalization 15 patients (mean age 78.18 ± 10.35 years); 80% male, 73% Sephardi descent developed respiratory failure rates of 60% occurring on average 10.6 days following intubation. Laboratory tests at admission displayed a significant increase in C-reactive protein (CRP) and creatine kinase (CK) and a decrease in absolute lymphocyte count (ALC) in patients who eventually developed respiratory failure (163.97 mg/L, 340.87 IU/L, 0.886 K/µl vs. 50.01 mg/L and 123.56 IU/L, 1.28 K/µl, respectively). Multivariate logistic analysis revealed an integrated parameter of CRP, CK, and ALC highly correlated with respiratory failure. Receiver operating characteristic curve revealed the area under the curve of CRP, CK, and ALC and the integrated parameter to be 0.910, 0.784, and 0.754, respectively. CRP was the strongest predictor to correlate with respiratory failure. CONCLUSIONS: CRP, CK, and ALC levels on admission could possibly be used to detect high-risk patients prone to develop respiratory failure.
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Infecções por Coronavirus/epidemiologia , Progressão da Doença , Serviço Hospitalar de Emergência/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Insuficiência Respiratória/mortalidade , Síndrome Respiratória Aguda Grave/diagnóstico , Síndrome Respiratória Aguda Grave/terapia , Centros Médicos Acadêmicos , Idoso , Idoso de 80 Anos ou mais , Proteína C-Reativa/análise , COVID-19 , Estudos de Coortes , Infecções por Coronavirus/prevenção & controle , Creatina Quinase/análise , Testes Diagnósticos de Rotina/métodos , Feminino , Humanos , Israel , Laboratórios Hospitalares/organização & administração , Modelos Logísticos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Avaliação de Resultados em Cuidados de Saúde , Pandemias/prevenção & controle , Pandemias/estatística & dados numéricos , Pneumonia Viral/prevenção & controle , Curva ROC , Insuficiência Respiratória/diagnóstico , Insuficiência Respiratória/terapia , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
INTRODUCTION: The Klausenberg Rebbe (Rabbi Yekutiel Yehudah Halberstam, of righteous memory) from the Sanz Chassidic dynasty, founded Sanz Medical Center - Laniado Hospital in 1976. He had lost his wife and eleven children in the Holocaust. The rabbi had a vision and initially received permission to open a maternity hospital to serve his community. Sanz Medical Center - Laniado Hospital is named after two brothers, Alphonse and Ya'akov Avraham Laniado, who were from the city of Haleb (Aleppo), Syria. They immigrated to Switzerland, where they managed a family bank. In their will, they specified that their estate be used to found a hospital named "Laniado" in Eretz Israel. The brothers provided the preliminary funds to found the hospital, while the remaining funds were collected by the Klausenberg Rebbe of the Sanz dynasty. In addition, a friends association has been established in Israel and around the world, headed by the "International Board of Trustees", which is responsible for the continued flow of funds to the various needs of the hospital. The hospital is a public non-profit institution under the supervision of an international board of trustees. The hospital is founded on Jewish law in every detail. Sanz Medical Center - Laniado Hospital never goes on strike, and treats every individual regardless of religion, race, or nationality. The medical center uses the most modern methods: its instruments, equipment, and expert staff have given the Sanz Medical Center its reputation as one of the leading hospitals in Israel. The Admor (the late Klausenberger Rebbe) expressed his vision for creating a hospital in his founding statement: "To strive as far as possible to ease the pain and suffering of the patients and to improve their emotional and spiritual state." Sanz Medical Center - Laniado Hospital has adopted as its motto the Admor's worldview: "The hospital will aid every person. In this hospital, the staff will work as professionals without forgetting the most important aspects of compassion, warmth, and empathy for the patient."
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Hospitais , Judaísmo , Criança , Feminino , Humanos , Israel , Masculino , Gravidez , SíriaRESUMO
Our objective was to assess risk factors for developing chronic immune thrombocytopenia (ITP) in children. The charts of all consecutive children diagnosed with ITP between 2000 and 2015 at a single center were retrospectively reviewed, and clinical characteristics at initial presentation were analyzed. Sixty-two children were included in the study (mean age, 6.15 y); 44 (71%) were found to have acute ITP, and 18 (29%) developed chronic ITP (permanent or relapsing thrombocytopenia >12 mo). In a univariate analysis, cutaneous hemorrhages were observed significantly more in acute patients (90.9%) than in chronic patients (61.1%). Patients who had acute ITP were more likely to present with a combination of petechiae, purpura, and/or ecchymosis (75%) than patients with chronic disease (44.4%, P=0.010). In multivariate analysis, older age increased the risk (odds ratio=1.1; P<0.05) for chronic disease, and manifestations of combination skin hemorrhages (petechiae/purpura/ecchymosis) reduced the risk (odds ratio=0.167; P<0.05). In conclusion, the most important risk factor for chronic disease is older age. Skin hemorrhage types were found to be a supportive factor for the prediction process: the combination of petechia/purpura/ecchymosis was associated with a lower risk for developing chronic disease compared with petechiae alone. Future studies should assess the prognostic value of skin hemorrhage types that are a simple way to predict the course of ITP in children.
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Púrpura Trombocitopênica Idiopática , Dermatopatias , Adolescente , Criança , Pré-Escolar , Doença Crônica , Feminino , Hemorragia/diagnóstico , Hemorragia/epidemiologia , Hemorragia/etiologia , Humanos , Masculino , Prognóstico , Púrpura Trombocitopênica Idiopática/complicações , Púrpura Trombocitopênica Idiopática/diagnóstico , Púrpura Trombocitopênica Idiopática/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Dermatopatias/diagnóstico , Dermatopatias/epidemiologia , Dermatopatias/etiologiaRESUMO
BACKGROUND: Immune thrombocytopenic purpura (ITP) is characterized by a transient (nonchronic) or permanent (chronic) decline in the number of platelets. Predicting the course of ITP, at the time of diagnosis, is of importance. Here we studied at diagnosis, clinical and immunological parameters in order to distinguish between different courses. The latter included the measure of new B and T cells using quantification of kappa-deleting recombination excision circles (KRECs) and T-cell receptor excision circles (TRECs), respectively. METHODS: Blood samples were collected from 44 children with a clinical diagnosis of ITP. Real-time PCR was performed in order to quantify the number of copies of TREC and KREC followed by collection of clinical data from medical files. The children were retrospectively divided into two groups: chronic and nonchronic. RESULTS: Twenty-four patients (54%) were classified as nonchronic ITP and 20 patients (46%) were classified as chronic ITP. We confirmed some clinical parameters (e.g., gender, age) but not others (e.g., preceding infection, level of thrombocytopenia) that distinguish patients with chronic and nonchronic course. While KREC quantification was similar in patients regardless the outcome of their disease, it was significantly higher than the level of controls (P < 0.05). TREC quantification was not different between patients and controls. CONCLUSIONS: KREC but not TREC levels are different in patients comparing to controls, pointing to an overreaction of B-cell development as a role in the pathogenesis of ITP. These results may shed more lights on the immune mechanism of ITP.
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Linfócitos B/imunologia , Biomarcadores/análise , Púrpura Trombocitopênica Idiopática/imunologia , Linfócitos T/imunologia , Adolescente , Criança , Pré-Escolar , Doença Crônica , Feminino , Humanos , Lactente , Masculino , Púrpura Trombocitopênica Idiopática/diagnóstico , Reação em Cadeia da Polimerase em Tempo RealRESUMO
Immune thrombocytopenia (ITP) in pregnant women can cause neonatal thrombocytopenia by transport of antiplatelet autoantibodies across the placenta. Usually, an infant's platelet count normalizes within 2 months. We observed neonatal thrombocytopenia that persisted more than 4 months and disappeared following discontinuation of breastfeeding. The aim of our study was to discern whether breast milk of ITP mothers contained antiplatelet antibodies causing persistent thrombocytopenia. We collected milk samples from 3 groups of women: ITP group, 7 women who had ITP during pregnancy; R-ITP group, 6 women who recovered from ITP before pregnancy; and 9 healthy controls. We found increased levels of antiplatelet antibodies of the immunoglobulin A type in the milk of ITP patients compared with the other 2 groups. Similar increase was demonstrated for antibodies binding to αIIbß3 expressed in cultured cells. Thus, transfer of antiplatelet antibodies from ITP mothers by breastfeeding can be associated with persistent neonatal thrombocytopenia.
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Autoanticorpos/metabolismo , Plaquetas/imunologia , Leite Humano/imunologia , Complicações Hematológicas na Gravidez/imunologia , Púrpura Trombocitopênica Idiopática/complicações , Trombocitopenia Neonatal Aloimune/etiologia , Adulto , Aleitamento Materno/efeitos adversos , Estudos de Casos e Controles , Células Cultivadas , Feminino , Humanos , Imunoglobulina A/metabolismo , Lactente , Recém-Nascido , Troca Materno-Fetal/imunologia , Contagem de Plaquetas , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/imunologia , Gravidez , Púrpura Trombocitopênica Idiopática/imunologia , Trombocitopenia Neonatal Aloimune/imunologiaRESUMO
BACKGROUND: Pandemic influenza A/H1N1 carries a relatively high morbidity, particularly in young people. Early identification would enable prompt initiation of therapy, thereby improving outcomes. OBJECTIVE: To describe the epidemiological, clinical and laboratory characteristics of children admitted to hospital with the clinical diagnosis of influenza with reference to pandemic influenza A/H1N1. METHODS: We conducted a prospective study of all children aged 16 years or less admitted to the pediatric department with the clinical diagnosis of influenza-like illness from July to October 2009. The presence of A/H1N1 virus was confirmed using real-time reverse transcriptase polymerase chain reaction (RT-PCR) analysis of nasopharyngeal secretions. Positive cases were compared with negative cases concerning epidemiological data, risk factors, clinical presentation and laboratory parameters, with emphasis on changes in the differential blood count. RESULTS: Of the 106 study patients, 53 were positive to influenza A/H1N1 and 53 were negative. In both groups nearly all patients had fever at presentation and approximately two-thirds had both fever and cough. All patients had a mild clinical course, no patient needed to be admitted to the intensive care unit and no mortalities were recorded. Hyperactive airway disease was more common in the A/H1N1-positive group. Pneumonia occurred in 30% of children in both groups. Laboratory findings included early lymphopenia and later neutropenia in theA/H1N1-infected patients. CONCLUSIONS: Leukopenia consisting of lymphopenia and later neutropenia was common in patients with A/H1N1 infection but was not correlated with disease severity or clinical course, which were similar in both groups. However, reduced leukocyte count can be used as an additional criterion for diagnosing A/H1N1 infection until RT-PCR results are available.