Infantile pyknocytosis, a neonatal hemolytic anemia with Heinz bodies: A cohort study.

Infantile pyknocytosis (IP) is a rare, probably misestimated, cause of non-immune neonatal hemolytic anemia evolving in two phases: an initial phase with severe jaundice, followed by a second phase with hemolytic anemia, which may require neonatal intensive care. The diagnosis of IP is based on the transient presence on blood smear of hyperdense, contracted, and/or spiculated red blood cells (pyknocytes), associated with the spontaneous resolution of clinico-biological features and the exclusion of other causes. If the etiology remains undetermined, some contributing factors, such as oxidative stress, have been proposed. We report the description of 16 patients with IP aiming at clarifying the circumstances associated with the development of this acquired disorder. In the acute phase, the mean hemoglobin nadir and pyknocyte count were 7.8 g/dL and 11%, respectively, and strikingly, Heinz bodies were evident in 50% of the newborns, but in 100% after prolonged incubation (4 hours). A high proportion of Mediterranean or African ancestry was noted in newborns, as well as a significant number of peripartum events, such as respiratory distress. If the etiology of IP is certainly multifactorial, our series reinforces the role of oxidative stress, which may, at least in part, find origin in desaturation episodes in newborns.

Heparin-induced thrombocytopenia: Construction of a pretest diagnostic score derived from the analysis of a prospective multinational database, with internal validation.

BACKGROUND: Diagnosis of heparin-induced thrombocytopenia (HIT) requires pretest probability assessment and dedicated laboratory assays. OBJECTIVE: To develop a pretest score for HIT. DESIGN: Observational; analysis of prospectively collected data of hospitalized patients suspected with HIT (ClinicalTrials.gov NCT00748839). SETTING: Thirty-one tertiary hospitals in France, Switzerland, and Belgium. PATIENTS: Patients tested for HIT antibodies (2280 evaluable), randomly allocated to derivation and validation cohorts. MEASUREMENTS: Independent adjudicators diagnosed HIT based on the prospectively collected data and serotonin release assay results. RESULTS: Heparin-induced thrombocytopenia was diagnosed in 234 (14.7%) and 99 (14.5%) patients in the two cohorts. Eight features were associated with HIT (in brackets, points assigned for score calculation of the score): unfractionated heparin (1); therapeutic-dose heparin (1); cardiopulmonary bypass (cardiac surgery) (2); major trauma (3); 5- to 21-day interval from anticoagulation initiation to suspicion of HIT (4); ≥40% decrease in platelet count over ≤6 days (3); thrombotic event, arterial (3) or venous (3). The C-statistic was 0.79 (95% CI, 0.76-0.82). In the validation cohort, the area under the receiver operating characteristic curve was 0.77 (95% CI, 0.74-0.80). Three groups of scores were defined; HIT prevalence reached almost 30% in the high-probability group. LIMITATION: The performance of the score may depend on settings and practices. CONCLUSION: The objective, easy-to-collect, clinical features of HIT we evidenced were incorporated into a pretest score, which may guide clinical decisions regarding diagnostic testing and anticoagulation.

Comparative Analysis of a French Prospective Series of 144 Patients with Heparin-Induced Thrombocytopenia (FRIGTIH) and the Literature.

BACKGROUND: Heparin-induced thrombocytopenia (HIT) is a rare complication of heparin treatments, and only a few large patient cohorts have been reported. In this study, biological and clinical data from 144 French patients with HIT were analyzed in comparison with the literature. METHODS: The diagnosis of HIT was confirmed in all patients by an immunoassay combined with serotonin release assay. In the literature, only cohorts of at least 20 HIT patients published from 1992 were selected for a comparative analysis. RESULTS: Two-thirds of patients were hospitalized in surgery and most were treated with unfractionated heparin (83.2% vs. 16.8% with low molecular weight heparin only). Thrombotic events in 54 patients (39.7%) were mainly venous (41/54). However, arterial thrombosis was more frequent after cardiac surgery (13.2% vs. 2.4% in other surgeries, p = 0.042) with a shorter recovery time (median = 3 vs. 5 days, p < 0.001). The mortality rate was lower in our series than in the 22 selected published studies (median = 6.3% vs. 15.9%). Three genetic polymorphisms were also studied and homozygous subjects FcγRIIA RR were more frequent in patients with thrombosis (37.8 vs. 18.2% in those without thrombosis, p = 0.03). CONCLUSION: This study shows that the mortality rate due to HIT has recently decreased in France, possibly due to earlier diagnosis and improved medical care. It also confirms the strong association between polymorphism FcγRIIA H131R and thrombosis in HIT.

An usual cause of elliptocytosis.

We report a 60-year-old adult case with a normocytic normochromic regenerative anemia discovered incidentally. The objectification of elliptocytosis accompanied by splenomegaly, a collagen myelofibrosis and the presence of the mutation JAK2V617F allowed the diagnosis of primary myelofibrosis with atypical initial presentation. The causes of elliptocytoses are discussed.

Internal carotid thrombus in patients with inflammatory bowel disease: two cases.

Increased ischemic stroke risk is observed in patients with inflammatory bowel disease (IBD). Causes and physiopathological aspects of cerebral infarct, in this specific population, are less often described. There is little information to provide guidelines for the best curative and preventive treatment. We report 2 cases of ischemic strokes due to internal carotid thrombus in patients during active phase of IBD. Ulceration of early atherosclerotic plaques activated by a hypercoagulation state may cause a thrombus. A combined therapy with heparin and corticosteroids was used for both our patients. Lysis of the thrombus was obtained after several days without surgical treatment and shown by ultrasonography. These cases highlight an aetiology of stroke in patients with IBD and use of a synergic treatment to respond to hypercoagulability in link with IBD. Benefits and safety of this therapy should be confirmed with clinical studies.

Polymorphonuclear neutrophils from JAK2(V617F) positive MPD patients do not support hypercoagulability: A study with calibrated automated thrombography (CAT).

Essential thrombocythemia and polycythemia vera are myeloproliferative disorders (MPD) with an elevated thrombotic risk. Leukocytosis has recently emerged as a new risk factor and there is increasing evidence that polymorphonuclear neutrophils (PMN) are involved. Procoagulant activity (PCA) of PMN in MPD has not yet been investigated. PCA of PMN from 22 patients with JAK2(V617F) positive MPD and 26 healthy subjects was studied using calibrated automated thrombography: in vitro thrombin generation induced with 1 pM tissue factor in the presence of added procoagulant phospholipids. There were no differences between patients and controls regarding the ability of PMN to increase thrombin generation. More surprisingly, basal thrombin generation in acellular MPD-plasma was found decreased for as yet unknown reasons. The presence of an active protein C pathway or platelets might provide a better insight into the coagulation phenotype in MPD.

Cerebral venous thrombosis due to essential thrombocythemia and worsened by heparin-induced thrombocytopenia and thrombosis.

This case describes the medical history of a 61-year-old woman treated for cerebral venous thrombosis (CVT) leading to diagnosis of essential thrombocythemia (ET). During treatment with unfractionated heparin, after initial improvement of clinical state, signs of cerebral hypertension reappeared. Although the platelet count decreased, heparin-induced thrombocytopenia (HIT) was only suspected 2 days later when it dropped below the standard 150 × 10(9) L(-1) threshold. HIT diagnosis was confirmed by the presence of anti-PF4/heparin IgG. This late finding was the cause of the extension of CVT with worsening of cerebral hypertension necessitating decompressive craniectomy. Elevated basal platelet count due to ET can delay diagnosis and treatment of HIT. In this case, physicians should be more attentive to platelet count variations rather than thrombocytopenia threshold.