Warfarin drug interaction with vitamin K and other foodstuffs / Interacción de la droga warfarina con la vitamina K y otros productos alimenticios

Vitamin K is found in higher concentrations in dark green plant and in vegetable oils. The adequate intake of vitamin K is 90 and 120ug/day for adult elderly men and women, respectively. The main function of vitamin K is to act as an enzymatic cofactor for hepatic prothrombin synthesis, blood coagulation factors, and anticoagulant proteins. Prominent among the many available anticoagulants is warfarin, an antagonist of vitamin K, which exerts its anticoagulant effects by inhibiting the synthesis of vitamin K1 and vitamin KH2. From the beginning of the therapy it is necessary that the patients carry out the monitoring through the prothrombin time and the international normalized ratio. However, it is known that very low intake and/or fluctuations in vitamin K intake are as harmful as high consumption. In addition, other foods can interact with warfarin, despite their content of vitamin K. The aim of this study was to gather information on the drug interaction of warfarin with vitamin K and with dietary supplements and other foods.

La vitamina K se encuentra en concentraciones más altas en plantas de color verde oscuro y en aceites vegetales. La ingesta adecuada de vitamina K es de 90 y 120 ug/día para hombres y mujeres adultos mayores, respectivamente. La función principal de la vitamina K es actuar como un cofactor enzimático para la síntesis de protrombina hepática, factores de coagulación de la sangre y proteínas anticoagulantes. Entre los muchos anticoagulantes disponibles destaca la warfarina, un antagonista de la vitamina K, que ejerce sus efectos anticoagulantes al inhibir la síntesis de la vitamina K1 y la vitamina KH2. Desde el inicio de la terapia, es necesario que los pacientes realicen el monitoreo a través del tiempo de protrombina y la proporción normalizada internacional. Sin embargo, se sabe que una ingesta muy baja y/o fluctuaciones en la ingesta de vitamina K son tan dañinas como un consumo alto. Además, otros alimentos pueden interactuar con la warfarina, a pesar de su contenido de vitamina K. El objetivo de este estudio fue recopilar información sobre la interacción de los medicamentos de la warfarina con la vitamina K y con los suplementos dietéticos y otros alimentos.

Prevención de hemorragias en el posoperatorio temprano de cirugía bariátrica: Papel de la vitamina K / Prevention of hemorrhage in the early postoperative period of bariatric surgery: Role of vitamin K

Introducción: la cirugía bariátrica es el tratamiento más eficaz para la obesidad mórbida. La hemorragia se presenta en el 0,5-5% de las pacientes. La preparación prequirúrgica con dieta líquida y el uso de antibióticos para Helicobacter pylori podría alterar el metabolismo de la vitamina K y asociarse a hemorragia. Objetivo: describir el comportamiento de la concentración de protrombina (basal = B-PT y prequirúrgica = preQ-PT) en estos pacientes. Material y métodos: se realizó un estudio de cohorte prospectivo donde se comparó la concentración de B-PT (15-180 días previos a la cirugía) y la preQ-PT (24 horas previas a la cirugía). Resultados: se incluyeron 194 pacientes, de los cuales el 72% (n = 139) fueron mujeres, de entre 19 y 69 años, con BMI (IMC) 45 (33 a 58) y pérdida de peso prequirúrgica del 7% (-2 a 17). El promedio de B-PT fue 91,9% (DE 9,529), el promedio de la preQ-PT fue 81,1% (DE 10,760); descendió un 10,8% (p < 0,001). No hubo diferencias significativas cuando se comparó el comportamiento en la preQ-PT entre los diferentes subgrupos (uso de antibióticos para Helicobacter pylori, de acuerdo con la pérdida de peso y en relación con la suplementación de vitamina K); sin embargo, siempre se detectó descenso de la preQ-PT. No hubo ninguna complicación hemorrágica (necesidad de transfusiones o reoperación); tampoco hubo muerte por hemorragias ni eventos tromboembólicos. Conclusión: realizar dosaje de protrombina 24 horas antes de la cirugía bariátrica permite detectar alteraciones iatrogénicas de la coagulación inducidas por la dieta y el uso de antibióticos.

Background: bariatric surgery is the most efficient treatment for morbid obesity. Bleeding occurs in 0.5-5% of patients. Pre-surgical preparation with liquid diet and the use of antibiotics for Helicobacter pylori could alter the metabolism of vitamin K and be associated with hemorrhage. Objective: to describe the behavior of the concentration of Prothrombin (basal = B-PT and pre-surgical = preQ-PT) in these patients. Material and methods: a prospective cohort study comparing B-PT concentration (15-180 days prior to surgery) and preQ-PT (24 h prior to surgery) was performed. Results: a total of 194 patients were included in the study, with 72% (n = 139) women aged 19-69 years, BMI 45 (33 to 58) and preoperative weight loss of 7% (-2 to 17). The media B-PT was 91.9% (SD 9.529), the media pre-PT was 81.1% (SD 10.760); declined 10.8% (p <0.001). There was no significant difference when comparing the behavior in the preQ-PT among different subgroups (use of antibiotics for Helicobacter pylori, according to weight loss and in relation to vitamin K supplementation), however, there was always a decrease of the preQ-PT. There were no bleeding complications (need for transfusions or re-intervetion), nor was there death for bleeding or thromboembolic events. Conclusion: prothrombin measurement 24 hours before bariatric surgery allows the detection of iatrogenic coagulation alterations induced by diet and the use of antibiotics.

Níveis de suplementação de vitamina K para codornas de corte em crescimento de 15 a 35 dias de idade / Vitamin K supplementation for meat quail in growth of 15 to 35 days old

O presente experimento foi realizado com o objetivo de determinar os níveis de suplementação de vitamina K para codornas de corte. O delineamento experimental foi inteiramente ao acaso, com oito tratamentos, cinco repetições e 38 codornas por unidade experimental. Os níveis de suplementação de vitamina K foram: 0; 0,7; 1,0; 1,3; 1,6; 1,9; 2,2; 2,5mg/kg de ração. Não houve influência dos níveis de suplementação de vitamina K sobre o consumo de ração, peso corporal, ganho de peso, biomassa corporal acumulada e conversão alimentar, como também não foram alterados o peso, a densidade óssea, a resistência óssea e a concentração de cinzas no fêmur e na tíbia, o comprimento e o índice de Seedor do fêmur e o diâmetro da tíbia. O diâmetro e a concentração de cálcio no fêmur bem como o comprimento e a concentração de cálcio na tíbia responderam de forma quadrática (P<0,05), sendo os melhores níveis encontrados de 1,33; 1,42; 1,59 e 1,42mg de vitamina K, respectivamente. O tempo de protrombina, a concentração de cálcio no soro e a fosfatase alcalina também não foram afetados significativamente. Conclui-se que os níveis de suplementação não influenciaram o desempenho, portanto rações à base de milho e farelo de soja são suficientes para atender às necessidades de vitamina K das codornas nessa fase.(AU)

An experiment was carried out in order to determine the levels of vitamin K for meat quails. The experimental design was completely randomized with 8 treatments, 5 repetitions and 38 quails per experimental unit. The levels of vitamin K supplementation were 0; 0.7; 1.0; 1.3; 1.6; 1.9; 2.2; 2.5 mg/kg diets. There was no influence in the levels of vitamin K supplementation on feed intake, body weight, weight gain, biomass accumulated body and feed conversion. It also didn't affect the weight, bone density, bone strength and concentration of ash in the femur and tibial, length, index of Seedor femur and tibial diameter. Femur diameter and femur calcium concentration and the tibial length and tibial calcium concentration showed a quadratic response, with the highest levels found 1.33; 1.42; 1.59 and 1.42 mg of vitamin respectively. Prothrombin time, concentration of serum calcium and alkaline phosphatase levels also were not significantly affected. In conclusion, levels of supplementation did not influence the performance of meat quails, so diets based on corn and soybean meal are sufficient to meet the needs of the meat quails at this stage.(AU)

Dientes natales: informe de un caso y revisión de la literatura / Natal teeth: report of a case and review of the literature

Cuando se encuentran dientes presentes al nacimiento es frecuente que los médicos pediatras interconsulten con el odontólogo, dichos dientes reciben el nombre de natales y neonatales de acuerdo con el momento en el cual hacen su aparición, si los dientes se encuentran presentes al nacimiento se les denomina natales y si aparecen durante el primer mes de vida se les llama neonatales. No es raro que los dientes natales y neonatales carezcan de raíz, y debido a su débil unión con eltejido gingival es posible que estos dientes puedan desalojarse y serbroncoaspirados o deglutidos por el menor durante la alimentación al seno materno. Si bien los dientes natales y neonatales no constituyen una entidad patológica per se, existen algunos síndromes genéticos que entre sus características se encuentran los dientes natales o neonatales.

When teeth are present at birth, pediatricians frequently seek the opinionof a dentist. These teeth are known as natal or neonatal depending onwhether they are present at birth or appear during the fi rst month oflife. It is not uncommon for natal and neonatal teeth to have no root,and due to their weak bond to the gingival tissue they can come looseand be breathed in or swallowed by the child during breast feeding.While natal and neonatal teeth are not a pathological entity per se,there are certain genetic syndromes whose features include natal orneonatal teeth.

Aspectos clínicos relacionados à anticoagulação oral em pacientes atendidos ambulatorialmente / Clinical aspects related to oral anticoagulation therapy in the outpatient setting

OBJETIVO: Comparar parâmetros clínicos relacionados aos pacientes em uso de varfarina sódica. MÉTODOS: Estudo retrospectivo, cujos dados foram buscados em prontuários e, em seguida, os pacientes foram categorizados em dois grupos: Grupo 1, composto por indivíduos que passaram por consultas nas quais apresentaram ao menos um episódio de valor de Coeficiente Internacional Normatizado (INR) abaixo do limite de normalidade, e Grupo 2, com ao menos uma dosagem de valor de INR acima do limite de normalidade. RESULTADOS: Foram incluídos 73 pacientes que totalizaram 363 consultas em uso de anticoagulante oral, sendo 42 pacientes homens. O intervalo médio entre as consultas foi de 36 dias. Quanto à etnia, a mais prevalente foi a branca, com 56,16%, e a escolaridade mais prevalente foi o primeiro grau completo (72,6%). As doses semanais de varfarina 5mg não diferiram entre as indicações de uso (F=0,218; p=0,953). CONCLUSÃO: Mais da metade das consultas estava fora da faixa terapêutica, demonstrando que a estratégia atual no atendimento clínico-ambulatorial tem suas limitações como o grande intervalo interconsultas e a dificuldade de comunicação com o paciente, seja pelo baixo grau de instrução ou pelo alto fluxo de pacientes. As interações medicamentosas e a interferência do sexo e de comorbidades nos valores de INR devem ser melhores avaliadas em estudos controlados

OBJECTIVE: To compare some clinical parameters related to patients taking warfarin sodium. METHODS: This is a retrospective study, the data of which was collected in medical records, with patients then being categorized into two groups: Group 1, consisting of individuals presenting for consultation who had at least one episode of an International Normalized Ratio (INR) value below the normal range, and Group 2, with at least one dose of INR values above the normal range. RESULTS: The study included 73 patients with a total of 363 visits, on oral anticoagulant therapy, with 42 patients b eing males. The average interval between visits was 36 days. As for ethnicity, the most prevalent was the white one with 56,16%, and the most prevalent educational level was primary school (72.6%). The weekly doses of warfarin 5mg did not differ within the indications of use (F=0.218, p=0.953). CONCLUSION: More than half of the visits were outside therapeutic range, demonstrating that the current strategy in clinical and ambulatory care has its limitations, such as the large interval between consultations, and the difficulty of communication with the patient, either because of the low educational level or the high flow of patients. Drug interactions, the interference of gender, and comorbidities

Ingestão acidental de brodifacoum por um cão / Brodifacoum accidental ingestion by a dog

Produtos utilizados para controle de roedores ocupam a terceira posição entre as causas mais comuns de exposições a agentes tóxicos em cães. Cerca de 20% dessas exposições resultam em intoxicação (OSWEILER, 1998). A terapêutica adequada e o tempo decorrido entre a ingestão e os primeiros procedimentos são os principais fatores determinantes do sucesso do tratamento, o qual pode ocasionar distúrbios de coagulação e morte do paciente, se não for bem conduzido. Este trabalho relata um caso de ingestão acidental de brodifacoum por um cão e a subsequente abordagem terapêutica emergencial.

[Hemorrhagic disease of newborn in children's hospital at damascus university and medical staff compliance to prophylactic vitamin k administration]

To determine the morbidity and mortality due to hemorrhagic disease of the newborn HDNB [vitamin K induced hemorrhagic disease] at Damascus University Children's Hospital [DUCH], and degree of medical staff compliance for applying related guidelines. A retrospective descriptive study of 307 patients with the diagnosis of HDNB at DUCH during 2000-2009. Ages ranged between 1 day and three months. Clinical, hematological and imaging studies were considered in all cases before final diagnosis of HDNB were established. A specimen of 307 patients were diagnosed having HDNB after the national guidelines for prophylactic vitamin K administration to newborns were established in 2000 by ministry of health. Early HDNB was found in 5.8%, classic HDNB in 14.3% and late HDNB in 78.8%. Home delivery contributed 32.9% of cases where hospital delivery 52.44% and private clinic delivery in 14.6%. Vitamin K injection after delivery was given in 14.2% [28 of 197] of well documented cases. Intra cranial hemorrhage was the most common complication especially in the late form of the disease 54.1%. Other hemorrhagic complications were as follows: skin 14.9%, gastrointestinal 18.6% and circumcision 8.7%. Death occurred in 23% of cases [n=71]; seizures occurred in 10% of survivors HDNB is still present as a cause of morbidity and mortality in newborn period and early infancy in area of the study; vitamin K administration at delivery is not a routine practice despite of clear national guidelines

Differences between uni-and multidimensional scales for assessing pain in term newborn infants at the bedside

OBJECTIVES: This study sought to determine the level of agreement between behavioral and multidimensional pain assessment scales in term newborn infants submitted to an acute nociceptive stimulus. METHODS: This cross-sectional study was performed on 400 healthy term newborns who received an intramuscular injection of vitamin K during the first 6 hours of life. Two behavioral pain scales (the Neonatal Facial Coding System and the Behavioral Indicators of Infant Pain) and one multidimensional tool (the Premature Infant Pain Profile) were applied by a single observer before the procedure, during cleansing, during injection and two minutes after injection. The Cochran Q, McNemar and kappa tests were used to compare the presence and degree of agreement between the three scales. The Hotelling T2 test was used to compare the groups of newborns for which the scales showed agreement or disagreement. A generalized linear regression was used to compare the results of the Neonatal Facial Coding System and the Behavioral Indicators of Infant Pain across the four study time points. RESULTS: The neonates studied had a gestational age of 39±1 weeks, a birth weight of 3169±316 g and and postnatal age of 67±45 minutes. During the stimulus procedure, 80% of the newborns exhibited pain behaviors according to the Neonatal Facial Coding System and the Behavioral Indicators of Infant Pain, and 70% experienced pain according to the Premature Infant Pain Profile (p<0.001). The frequencies of the detection of pain using the Behavioral Indicators of Infant Pain and the Neonatal Facial Coding System were similar. The characteristics of the neonates were not associated with the level of agreement between the scales. CONCLUSION: The Neonatal Facial Coding System and the Behavioral Indicators of Infant Pain behavioral scales are more sensitive for the identification of pain in healthy term newborn infants than the multidimensional Premature Infant Pain Profile scale.

Administración oral de preparado parenteral de vitamina K en anticoagulación excesiva por warfarina / Oral administration of intravenous preparation of Vitamin K for excessive anticoagulation due to warfarin

La warfarina es frecuentemente usada en la terapia anticoagulante actual, su acción debe ser monitorizada usando el tiempo de protrombina expresado como International Normalized Ratio (INR); cuando se excede el rango de seguridad se puede administrar vitamina K (Vit-K), preferentemente por vía oral. Dicha presentación no está disponible en Venezuela. Se realizó un ensayo clínico, doble ciego, donde a 20 pacientes, edad 18-60 años, sin sangrado e INR inicial de 6 a 10 inclusive; les fue suspendida la warfarina e inmediatamente agrupados al azar a recibir dosis única de Vit-K (oral 1.25mg de Vit-K fraccionada de una presentación parenteral) o placebo. El punto final primario, INR < 3.5 a las 24 horas de administrar la dosis, se alcanzó en 70% de los pacientes en Vit-K y 20% en placebo. La reducción absoluta del riesgo y su intervalo de confianza de 95%: RAR (IC95%) = 50% (14.4 a 85.6) ρ = 0.028; NNT (IC95%) = 2(1.3 a 6.9); no se registraron eventos adversos, ni INR < 2 luego de 24 horas de tratamiento. Los resultados obtenidos son consistentes con estudios donde se administró Vit-K en preparación específica para vía oral. Así la Vit-K en presentación parenteral, administrada por vía oral, es más efectiva y segura que simplemente detener la administración de warfarina para revertir la excesiva anticoagulación, en donde no exista presentación específica oral de Vit-K o ésta sea muy costosa.

Anticoagulation therapy with warfarin, a common clinical practice, needs to be monitored using protombine time expressed as the International Normalized Ratio (INR); when safety range is exceeded, Vitamin K (Vit-K) could be administered with preference orally. In Venezuela the specific oral preparation for Vit-K is not available. This is a double blinded, randomized, placebo controlled, clinical trial; 20 patients, age 18-60 year with initial INR ≥ 6, ≤10, were randomized to oral Vit-K 1.25mg (prepared from intravenous presentation) or placebo plus withholding warfarin. INR < 3.5 at 24 hours of treatment (the primary end point) was achieved by 70% among Vit-K, and 20% among placebo patients; given an absolute risk reduction (ARR), of 50% (CI95%: 14.4-85.6) ρ = 0.028, NNT 2 (CI95%: 1.3 - 6.9). No adverse events were recorded including INR < 2 at 24 hours of treatment administration. Our results are consistent with studies where specific oral presentation of Vit-K was used. The results indicate that oral administration of Vit-K, prepared from an intravenous Vit-K preparation, is safe and more effective to revert excessive anticoagulation than simply withholding warfarin, in places where specific preparation of oral Vit-K is not available or too expensive.

Influências da vitamina K em pacientes cardiopatas usuários de anticoagulantes orais e o gene CYP2C9 / Influence of vitamin K in cardiac patients taking oral anticoagulants and CYP2C9

As orientações nutricionais são restritivas quanto aos alimentos ricos em vitamina K com intuito de um controle adequado do International Normalized Ratio (INR). Avaliamos o consumo de alimentos ricos em vitamina K, sua relação com o nível sérico dessa vitamina e o INR de 66 pacientes cardiopatas usuários de varfarina. A idade média foi de 61 anos (DP = 11,71). O consumo de vitamina K foi abaixo do recomendado em 74% dos pacientes no RGA 7 dias. No QFA, o consumo de verduras e legumes verdes escuros era abaixo de três vezes por semana. Não encontramos relação no tipo de óleo consumido com os níveis séricos de vitamina K. A vitamina K plasmática observada foiu em média de 0,54 ng/mL. Não houve correlação entre a ingestão de vitamina K e o INR desses pacientes, assim como não houve diferença na ingestão ou dos níveis séricos em relação à idade. A orientação nutricional restritiva a alimentos ricos em vitamina K estava relacionada a níveis séricos abaixo dessa vitamina, sendo importante estabelecer a consequência dessa condição sobre outros aspectos da saúde desses pacientes. As variações observadas no INR desses pacientes foram independentes dos níveis séricos de vitamina K, sugerindo uma supervalorização da dieta como um fator desestabilizador. Confirmamos, no nosso estudo, que a proporção de pacientes com genótipo CYP2C9 é a esperada para a população. Porém, não encontramos diferença significativa na dose atual diária dos pacientes nos genótipos variantes do CYP2C9, assim como no INR.

Vitamin K Supplement Along with Vitamin D and Calcium Reduced Serum Concentration of Undercarboxylated Osteocalcin While Increasing Bone Mineral Density in Korean Postmenopausal Women over Sixty-Years-Old

There are inconsistent findings on the effects of vitamin K on bone mineral density (BMD) and undercarboxylated osteocalcin (UcOC). The present intervention study evaluated the effect in subjects over 60-yr-old. The vitamin K group (vitamin K + vitamin D + calcium supplement; 15 mg of vitamin K2 [menatetrenone] three times daily, 400 IU of vitamin D once a day, and 315 mg of calcium twice daily) and the control group (vitamin D + calcium supplement) were randomly assigned. During the six months of treatment, seventy eight women participated (38 in the vitamin K group and 40 in the control group) and 45 women completed the study. The baseline characteristics of study participants did not differ between the vitamin K and the control groups. In a per protocol analysis after 6 months, L3 bone mineral density has increased statistically significantly in the vitamin K group compared to the control group (0.01 +/- 0.03 g/cm2 vs -0.008 +/- 0.04 g/cm2, P = 0.049). UcOC concentration was also significantly decreased in the vitamin K group (-1.6 +/- 1.6 ng/dL vs -0.4 +/- 1.1 ng/dL, P = 0.008). In conclusion, addition of vitamin K to vitamin D and calcium supplements in the postmenopausal Korean women increase the L3 BMD and reduce the UcOC concentration.

Adrenal hemorrhage due to vitamin-K deficiency.

Adrenal hemorrhage has many etiologies including bleeding diathesis. A 10-day-old female baby was admitted to our clinic with the complaint of abdominal distention. Hemorrhage was determined on the right adrenal gland with abdominal ultrasonography and computerized tomography. Laboratory investigations showed PT 44 sec and aPTT longer than one minute. This article reports here an infant diagnosed as adrenal hemorrhage due to Vitamin-K deficiency presenting as an abdominal mass.

Rosacea: tratamiento con vitamina K topica / Rosacea: vitamin K therapy

La rosácea es una dermopatía que afecta selectivamente la cara, caracterizada por la aparición sucesiva o simultánea de eritema, telangiectasias, pápulas y pústulas, siendo el eritema su sustrato obligado y las dilaciones vasculares una etapa de comienzo. Se realiza un ensayo terapéutico con vitamina K en forma de máscara y en crema para uso diario con una respuesta eficaz en la disminución del eritema

Hemorragia intracraniana por deficiência de vitamina k em lactentes - relato de 2 casos / Intra-cranial hemorrhage in infants due to vitamin k deficiency - report of 2 cases

Objetivo: Chamar a atenção para a forma tardia da doença do recém-nascido secundária à deficiência de vitamina k, como causa de hemorragia intracraniana em lactentes jovens. Métodos: Os autores descrevem e analisam dois casos de doença hemorrágica tardia do recém-nascido, por deficiência de vitamina k, com hemorragia intracraniana no segundo mês de vida. As principais publicações sobre o tema foram revisadas. Resultados: Ambos os lactentes não haviam recebido profilaxia com vitamina k ao nascimento e vinham sendo alimentado exclusivamente com leite materno. Desenvolveram hemorragia intracraniana, e a coagulopatia foi rapidamente corrigida com administração de vitamina k por via intramuscular. Aos 3 e 4 anos de idade, um deles apresenta desenvolvimento psicomotor normal e o outro, atraso psicomotor moderado com microcefalia. Conclusão: A doença hemorrágica do recém-nascido deve ser considerada em lactentes jovens, entre 2 e 12 semanas de vida, com hemorragia intracraniana, sobretudo quando são alimentados exclusivamente com leite materno e não receberam vitamina k ao nascimento. Pode produzir seqüelas neurológicas. A coagulopatia é rapidamente corrigida com vitamina k e é passível de prevenção. Recomenda-se a profilaxia em todo o recém-nascido, logo ao nascimento, com a adminstraçao de 1 mg da viatmaina por via intramuscular

Medicina hoy: presente y futuro de los anticoagulantes orales / Medicine today: present and future of oral anticoagulants

El número de pacientes bajo tratamiento anticoagulante oral se ha incrementado notablemente en los últimos años al incorporarse la población de pacientes con fibrilación auricular crónica. Su manejo se ha facilitado al contar actualmente con reactivos comerciales sensibles y calibrados. No obstante este avance, las complicaciones hemorrágicas siguen siendo uno de los peligros de este tratamiento. En nuestra experiencia, las hemorragias mayores se correlacionan sobre todo con la intensidad de la anticoagulación y la duración del tratamiento. También la variabilidad del RIN (Razón Internacional Normatizada) (la desviación del RIN del rango deseado) puede asociarse con mayor sangrado. La necesidad de ajustar la dosis con pruebas de laboratorio, los controles frecuentes, la interacción con otras medicaciones, la estrecha ventana terapéutica y la alta variación en la relación dosis-respuesta, hacen surgir la necesidad de nuevos agentes antitrombóticos, igualmente eficaces, pero que permitan prescindir del ajuste por el laboratorio. Inhibidores de trombina de bajo peso molecular disponibles por vía oral están actualmente en período de prueba y constituirían una alternativa al tratamiento con antagonistas de vitamina K.

Colapso cardiovascular agudo después de la administración de vitamina K / Cardiovascular collapse secondary to phytonadione administration: A case report

Introducción. En diversas circunstancias se administra vitamina K; se ha reportado que puede ocasionar diversos efectos adversos. El objetivo del presente caso es reportar que la vitamina K administrada en forma intravenosa (IV) puede asociarse a colapso vascular. Caso clínico. Femenino de 9 años de edad que requirió hospitalización prolongada por pancreatitis postraumática. Por ayuno prolongado se le inició manejo con vitamina K IV. A los 22 días de su ingreso y con previa estabilidad hemodinámica desarrolló hipotensión y colapso vascular requiriendo líquidos IV y aminas; se descartó origen metabólico y cardiopulmonar del evento que se recuperó totalmente. Los medicamentos que recibía entonces eran vitamina K presentó hipotensión, desaturación, prurito, hiperemia conjuntival y colapso vascular, requiriendo nuevamente líquidos en carga IV y aminas con recuperación exitosa en 3 horas. Se suspendió la vitamina K mientras continuó recibiendo los otros medicamentos que tenía previamente. La paciente fue dada de alta en buen estado general. Conclusión. Aunque es una reacción rara, la administación IV de vitamina K puede ocasionar reacciones graves incluyendo colapso vascular

Vitamin K deficiency bleeding in Thailand: a 32-year history.

Vitamin K deficiency bleeding cases in Thailand from 1963 to 1995 were extensively studied. From 1963 to 1987 there were 499 reported cases from 10 papers including 102 cases of the authors' series. From March 1994 to April 1996, two subsequent nationwide surveys were conducted where questionnaires were sent to 714 and 732 hospitals located throughout Thailand. The responding rate was 58.2% and 67% respectively. 331 cases were found during 1988 to 1995. The total number was 830 cases of which 799 were idiopathic vitamin K deficiency in infancy (IVKDI) and 31 were secondary types. IVKDI was found exclusively breast-fed infants (92%) who did not receive vitamin K prophylaxis at birth (90%). Bleeding and pallor were the common features. The occurrence of intracranial hemorrhage was strikingly high (82%); the fatality rates was 24%. However, the fatality rate among patients receiving either 1 mg of vitamin K, intramuscularly, (17%) or 2 mg, orally, (18%) were lower than those not receiving vitamin K prophylaxis (36%). The incidence of IVKDI significantly declined to 4.2-7.8 per 100,000 births between 1988 to 1995 which was in reverse proportion to the coverage of vitamin K prophylaxis (r = -0.94, p < 0.05).

La vitamina K: bioquímica, función y deficiencia: revisión / The vitamin K: biochemistry, function and deficiency: riview

La vitamina K es un cofactor que actúa en la síntesis de los factores de coagulación II, VII, IX y X, de los inhibidores de la coagulación, proteínas C y S, y de proteínas de la matriz ósea. Su forma activa actúa como coenzima en la carboxilación del ácido glutámico de dichas proteínas. La función de los factores dependientes de la vitamina K se realizan mediante la formación de complejos enzimaticos, en los cuales estas proteínas se unen sobre la membrana fosfolipídica a un cofactor proteíco, en presencia de calcio. La insuficiencia de los mecanismos responsables de la gamma-carboxilación del ácido glutámico altera la función hemostática. La deficiencia hereditaria de factores dependientes de vitamina K, los antibióticos y los anticoagulantes orales disminuyen la capacidad de formación de los complejos enzimaticos, por lo que se produce síndrome hemorrágico o trombóticos y alteraciones de la masa ósea que son fácilmente tratadas con administración de preparados de vitamina K. Las causas principales de deficiencia son: falta de reservas hepáticas en recién nacidos, insuficiencia hepática, falta de ingesta, malabsorción, antibioticoterapia y admisnistración de cumarínicos. Para el estudio de la vitamina K se usan métodos indirectos, que miden las proteínas dependientes de su acción, y métodos directos que miden específicamente las quinonas