Association of non-malignant diseases with thrombocytosis: a prospective cohort study in general practice.

BACKGROUND: Thrombocytosis is an excess of platelets, which is diagnosed as a platelet count >400 × 109/l. An association of thrombocytosis with undiagnosed cancer has recently been established, but the association with non-malignant disease has not been studied in primary care. AIM: To examine, in English primary care, the 1-year incidence of non-malignant diseases in patients with new thrombocytosis and the incidence of pre-existing non-malignant diseases in patients who develop new thrombocytosis. DESIGN AND SETTING: Prospective cohort study using English Clinical Practice Research Datalink data from 2000 to 2013. METHOD: Newly incident and pre-existing rates of non-malignant diseases associated with thrombocytosis were compared between patients with thrombocytosis and age- and sex-matched patients with a normal platelet count. Fifteen candidate non-malignant diseases were identified from literature searches. RESULTS: In the thrombocytosis cohort of 39 850 patients, 4579 (11.5%) were newly diagnosed with any one of the candidate diseases, compared with 443 out of 9684 patients (4.6%) in the normal platelet count cohort (relative risk [RR] 2.5, 95% confidence intervals [CI] = 2.3 to 2.8); iron-deficiency anaemia was the most common new diagnosis (4.5% of patients with thrombocytosis, RR 4.9, 95% CI = 4.0 to 6.1). A total of 22 612 (57.0%) patients with thrombocytosis had a pre-existing non-malignant diagnosis compared with 4846 patients (50%) in the normal platelet count cohort (odds ratio 1.3, 95% CI = 1.2 to 1.4). There was no statistically significant difference in cancer diagnoses between patients with and without pre-existing disease in the thrombocytosis cohort. CONCLUSION: Thrombocytosis is associated with several non-malignant diseases. Clinicians can use these findings as part of their holistic diagnostic approach to help guide further investigations and management of patients with thrombocytosis.

HEMATOLOGICAL INDICES IN AUTOMOTIVE TECHNICIANS IN NNEWI, SOUTH-EAST NIGERIA.

BACKGROUND: Occupational exposure to petroleum products is known to be associated with a number of health risks as well as adverse effects on haematological indices. OBJECTIVE: To evaluate the effect of exposure to petroleum products on haematological parameters in automobile mechanics in Nnewi, south-east Nigeria. SUBJECTS AND METHODS: Fifty (50) automobile technicians and 50 healthy controls participated in the study. Full blood count was performed for each participant using the automated Sysmex haemocytometer (Model PCE 210) while data analysis was done using the SPSS (statistical package for social sciences) version 16 computer soft ware (Chicago, IL, Inc.). Results were expressed as frequencies, means and standard deviations; comparison of haematological parameters was made between subjects and controls and at different durations of exposure using the students' t-test and analysis of variance (ANOVA), respectively. The level of statistical significance was p < 0.05 (at 95% CI). Ethical approval was obtained from the Institutional review board and all participants gave informed consent. RESULTS: There red blood cell count (RBC) and haematocrit were significantly lower while the platelet count was significantly higher in test subjects compared with controls (p values; 0.04, 0.03 and 0.01, respectively). Correspondingly, the mean cell volume (MCV) and mean cell haemoglobin (MCH) were significantly lower in test subjects compared with controls (p = 0.62 and 0.03, respectively). The red cell count, MCV and platelet count significantly decreased with increasing duration of work exposure (p = 0.001, respectively). CONCLUSION: Occupational exposure to petroleum products adversely affects blood counts, with a significant decrease in RBC, MCV and platelet count as duration of exposure increases.

Thrombocytosis in neonates and young infants: a report of 25 patients with platelet counts of > or = 1000000 microl(-1).

OBJECTIVE: Thrombocytosis has been reported in neonates and young infants, but little is known of its prevalence, timing of onset, associated conditions, sequelae and outcomes. To better understand this condition, we used the data repositories of a multi-hospital health-care system to identify all individuals or=1000000 microl(-1). STUDY DESIGN: We identified all infants with extreme thrombocytosis (using the Sutor definition of a platelet count of >or=1000000 microl(-1)) during the period of January 2003 through December 2008 in any Intermountain Healthcare facility. We obtained the information provided in this report from electronic and paper records. RESULT: Among 40 471 infants who had one or more platelet counts performed in this period, 25 had extreme thrombocytosis. No cases were identified in the first week after birth, 40% were recognized between the second and fourth weeks and 40% between the fifth and eighth week. The prevalence of thrombocytosis had no relationship with birth weight or gestational age but a slight predominance of female patients (15/25) was noted. In all, 26 episodes were found among the 25 infants: 12 episodes involved an antecedent infectious disease, 8 had an antecedent surgical procedure, 4 had the anemia of prematurity and 1 each had congenital adrenal hyperplasia and opiate withdrawal syndrome. No pathological thromboses or hemorrhages or other sequelae were detected and all episodes resolved with no deaths. CONCLUSION: The thrombocytosis cases that we report were all consistent with reactive thrombocytosis (also known as secondary thrombocytosis); none seemed to be essential (primary) thrombocytosis. We speculate that the pathogenesis involves increased platelet production due to megakaryopoietic stimulators induced by an infectious or inflammatory condition. From this series and previous reports, young infants with platelet counts up to 1300000 microl(-1) do not seem to have a significant risk of thrombotic or hemorrhagic problems, and do not generally require anti-platelet or cytoreductive treatment.

[Thrombocytosis in the oncology-haematology clinic: description, aetiological diagnosis and progression thrombocytosis]. / Trombocitosis en la consulta de oncohematología. Descripción, diagnóstico etiológico y evolución.

INTRODUCTION: Thrombocytosis is a common cause of patient referral to a paediatric haematologist specialist which requires a significant number of laboratory tests and visits to confirm the diagnosis. The aim of our study has been to analyse the characteristics of patients referred to our centre for specialised thrombocytosis assessment. Based on this assessment we established the criteria patients must fulfil to be recommend for further hospital study. PATIENTS AND METHODS: We categorised the 33 patients referred for thrombocytosis assessment according to sex, age, origin, personal and family history, platelet count at diagnosis and the reason why the red and white blood count at diagnosis (Haemoglobin, mean corpuscular volume, mean corpuscular haemoglobin, leukocyte, neutrophils, lymphocyte and monocyte count), maximum platelet count during follow-up and other complementary examinations were done. The final diagnosis itself and number of previous visits before were also considered. The classification used to grade thrombocytosis was: low (500-700 X 10(3)/microl), mild (700-900 x 10(3)/microl), severe (900-1.000 x 10(3)/microl) and extreme (> 1.000 x 10(3)/microl). RESULTS: There was no predominance of males or females. 45 % of patients were under 2 years old and 55 % of them came from their primary care centre. The mean platelet count at the first medical visit was 669,000 (mild thrombocytosis). During follow-up, 24 % of the patients reached extreme platelets levels. In 28 % the initial blood count was performed because of an infection. The most frequently requested laboratory test was iron metabolism (82 % of the cases). All cases correspond to secondary thrombocytosis (48 % were reactive to infections, 24 % secondary to iron deficiency, and 15 % were associated to both causes). The mean number of visits before hospital discharge was 5.12. CONCLUSIONS: The finding of thrombocytosis in the majority of the cases studied was casual or in the context of an infectious process. Most of the thrombocytosis were mild. Due to the extremely low incidence of primary thrombocytosis in childhood and the fact that diagnosis is made by exclusion of other possibilities, the initial study of these patients should be done in primary care centres. The first conditions to be ruled out are infectious, inflammatory or bleeding processes. Once these causes are excluded, the most useful complementary test is to measure iron level given the relation between iron deficiency and thrombocytosis. Once these causes are ruled out and thrombocytosis persists, it would then be indicated to refer the patient to a paediatric oncology-haematology department for a more exhaustive follow-up.

Trombocitosis en la consulta de oncohematología. Descripción, diagnóstico etiológico y evolución / Thrombocytosis in the oncology-haematology clinic: Description, aetiological diagnosis and outcome

Introducción: La trombocitosis es un motivo frecuente de consulta en oncohematología infantil, y precisa un importante número de visitas y determinaciones analíticas para su diagnóstico o resolución. Nuestro objetivo ha sido evaluar las características de los pacientes derivados a nuestro servicio en los últimos meses para estudio de trombocitosis y establecer cuáles deberían ser los pacientes que precisan un estudio más exhaustivo en el hospital. Pacientes y métodos: Se determina en 33 pacientes derivados por este motivo el sexo, el rango de edad, la procedencia, los antecedentes personales y familiares, el grado de trombocitosis por la que se consulta y la cifra máxima durante el seguimiento, el motivo por el que se realiza la primera analítica, los valores hematimétricos en la primera analítica (hemoglobina [Hb], volumen corpuscular medio [VCM], hemoglobina corpuscular media [HCM], leucocitos [linfocitos y neutrófilos]), las exploraciones complementarias realizadas, el diagnóstico y el número de visitas que precisaron antes del alta. Se clasifica la trombocitosis en leve (500-700 × 103/μl), moderada (700-900 × 103/μl), grave (900-1.000 × 103/μl) y extrema (> 1.000 × 103/μl). Resultados: No hubo predominancia de sexos. El 45 % de los pacientes eran menores de 2 años. Procedían en un 55 % de su centro de salud. La cifra media de plaquetas por la que consultaron fue de 669.000 (trombocitosis leve). En el seguimiento llegaron a cifras extremas el 24 %. En el 28 % la analítica se había realizado por un cuadro infeccioso. La exploración complementaria más solicitada fue el metabolismo del hierro (en el 82 %). Todos se corresponden con trombocitosis secundarias (el 48 % reactivas a infecciones, el 24 % secundarias a ferropenia y el 15 % por ambas causas). El número medio de visitas ha sido de 5,12. Conclusiones: El hallazgo de la trombocitosis es en la mayoría de los casos casual o en el contexto de un cuadro infeccioso y, además, son leves. Dada la baja incidencia de trombocitosis primaria en la infancia y que el diagnóstico es de exclusión, se debería iniciar el estudio de la misma en la consulta de atención primaria, descartando inicialmente una causa infecciosa, inflamatoria o secundaria a sangrado. Una vez descartadas estas causas la prueba complementaria más rentable es el metabolismo del hierro, dada la asociación de ferropenia con trombocitosis. Si también se excluye esta etiología y se comprueba la persistencia de la trombocitosis, estaría indicado derivar al paciente a un servicio de oncohematología infantil para completar estudio (AU)

Introduction: Thrombocytosis is a common cause of patient referral to a paediatric haematologist specialist which requires a significant number of laboratory tests and visits to confirm the diagnosis. The aim of our study has been to analyse the characteristics of patients referred to our centre for specialised thrombocytosis assessment. Based on this assessment we established the criteria patients must fulfil to be recommend for further hospital study. Patients and methods: We categorised the 33 patients referred for thrombocytosis assessment according to sex, age, origin, personal and family history, platelet count at diagnosis and the reason why the red and white blood count at diagnosis (Haemoglobin, mean corpuscular volume, meen corpuscular haemoglobin, leukocyte, neutrophils, lymphocyte and monocyte count), maximum platelet count during follow-up and other complementary examinations were done. The final diagnosis itself and number of previous visits before were also considered. The classification used to grade thrombocytosis was: low (500-700 × 103/μl), mild (700-900 × 103/μl), severe (900-1.000 × 103/μl) and extreme (> 1.000 × 103/μl). Results: There was no predominance of males or females. 45 % of patients were under 2 years old and 55 % of them came from their primary care centre. The mean platelet count at the first medical visit was 669,000 (mild thrombocytosis). During follow-up, 24 % of the patients reached extreme platelets levels. In 28 % the initial blood count was performed because of an infection. The most frequently requested laboratory test was iron metabolism (82 % of the cases). All cases correspond to secondary thrombocytosis (48 % were reactive to infections, 24 % secondary to iron deficiency, and 15 % were associated to both causes). The mean number of visits before hospital discharge was 5.12. Conclusions: The finding of thrombocytosis in the majority of the cases studied was casual or in the context of an infectious process. Most of the thrombocytosis were mild. Due to the extremely low incidence of primary thrombocytosis in childhood and the fact that diagnosis is made by exclusion of other possibilities, the initial study of these patients should be done in primary care centres. The first conditions to be ruled out are infectious, inflammatory or bleeding processes. Once these causes are excluded, the most useful complementary test is to measure iron level given the relation between iron deficiency and thrombocytosis. Once these causes are ruled out and thrombocytosis persists, it would then be indicated to refer the patient to a paediatric oncology-haematology department for a more exhaustive follow-up (AU)