Abstract Number: PB0800
Meeting: ISTH 2020 Congress
Theme: Hemophilia and Rare Bleeding Disorders » Disseminated Intravascular Coagulation
Background: Coagulation abnormalities, a well-known complication of hemophagocytic lymphohistiocytosis (HLH), occur in up to 2/3 of adult patients and are associated with increased mortality. Data is lacking in pediatric patients.
Aims: To describe the incidence and characteristics of coagulopathy in pediatric patients presenting with HLH.
Methods: Retrospective chart review was performed on patients 0-21 years of age meeting the required 5/8 HLH diagnostic criteria with evaluation of at least one coagulation parameter from 2006-2019. Coagulopathy was assessed from laboratory results and defined as international normalized ratio (INR)>1.5, ≥10% prolongation of partial thromboplastic time (PTT) from upper limit of normal (ULN), fibrinogen < 1g, or D-dimer > 3xULN.
Results: 56 patients were identified, with a median age of 8 years [IQR 0-16, STD 7.5]. 95% of patients had thrombocytopenia. 84% of patients had laboratory evidence of coagulopathy. Fibrinogen was obtained in all patients while PT, PTT and D-dimer were less frequently measured (95%, 95% and 54% respectively). Of those evaluated, D-dimers were abnormal 97% of the time, PTT 74% of the time, fibrinogen 63%, and PT 57%. Bleeding and thrombotic complications were less commonly seen than laboratory evidence of coagulopathy (34% and 16% respectively). Mortality was 43% and was associated with lower platelet count at presentation and nadir (p=0.04 and p=0.003 respectively), peak INR (p=0.01), fibrinogen at nadir (p=0.01), peak ISTH DIC score (p=0.03), major bleeding (p=0.03) and ferritin (p=0.03). Patients with laboratory evidence of coagulopathy and patients with major bleeding were significantly more likely to die than those without (OR 19.8, 95% CI 1.09-359.87, p=0.04, OR 4.2, 95% CI 1.1-15.95, p=0.04 respectively).
Conclusions: Coagulopathy is seen in the majority of pediatric patients with HLH and is associated with increased mortality. Coagulation parameters should be fully assessed in these patients and may help inform prognosis.
| Platelets <150,000 | Fibrinogen>1g | INR ≥1.5 | PTT prolongation >10% | D-dimer elevation | |
| Measured | 56 | 56 | 53 | 53 | 30 |
| Presenting | 45 (80%) | 11 (20%) | 18 (34%) | 28 (53%) | 28 (93%) |
| Developed | 8 (14%) | 24 (43%) | 12 (23%) | 11 (21%) | 1 (3%) |
| Total | 53 (95%) | 35 (63%) | 30 (57%) | 39 (74%) | 29 (97%) |
[Laboratory Assessment of Coagulopathy]
| Surviving (n=32) | Decreased (n=24) | P-value | |
| Platelets (mean, presentation) | 128,344 | 72,833 | 0.04 |
| Platelets (mean, nadir) | 70,188 | 19,479 | 0.003 |
| INR (mean, peak) | 1.74 | 2.64 | 0.01 |
| Fibrinogen (mean, nadir) | 151.3 | 91.4 | 0.01 |
| ISTH DIC score (mean, peak) | 6.00 | 7.31 | 0.03 |
| Thrombosis (%) | 12.5% (4/32) | 21% (5/24) | 0.40 |
| All Bleeding (%) | 25% (8/32) | 46% (11/24) | 0.10 |
| Major bleeding (%) | 12.5% (4/32) | 37.5% (9/24) | 0.03 |
| Ferritin | 8,349 | 22,924 | 0.03 |
[Coagulation parameters of surviving and deceased patients]
To cite this abstract in AMA style:
Shamoun M, Walkovich K, Weyand A. Coagulopathy in Pediatric Patients with Hemophagocytic Lymphohistiocytosis [abstract]. Res Pract Thromb Haemost. 2020; 4 (Suppl 1). https://abstracts.isth.org/abstract/coagulopathy-in-pediatric-patients-with-hemophagocytic-lymphohistiocytosis/. Accessed May 16, 2021.« Back to ISTH 2020 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/coagulopathy-in-pediatric-patients-with-hemophagocytic-lymphohistiocytosis/