Characteristics of patients with discordant ELISA and CLIA results
| Patient no. . | 1 . | 2 . | 3 . | 4 . | 5 . |
|---|---|---|---|---|---|
| Age, y | 75 | 66 | 63 | 71 | 56 |
| Sex | M | F | M | F | M |
| BMI, kg/m2 | 37 | 30 | 23 | 25 | 28 |
| ECMO | No | No | No | No | No |
| Renal function | |||||
| CrCl, mL/min | 115 | 44 | 127 | 80 | 111 |
| Dialysis at the time of HIT diagnosis | No | Yes | No | No | No |
| Heparin therapy | |||||
| Indication | Heart valve surgery and AF | Heart valve surgery | Aortic thrombosis | DVT | Heart valve surgery |
| Type | UFH | UFH | UFH | UFH | UFH |
| HIT diagnosis | |||||
| 4Ts score | 5 | 6 | 5 | 7 | 4 |
| Delay since heparin initiation, d | 7 | 10 | 10 | 6 | 15 |
| HITT | None | Extension of preexisting thrombosis (jugular vein) + dialysis filter thrombosis | None | Extension of preexisting thrombosis | None |
| IgG PF4/H (OD)∗ ELISA | 1.513 | 1.145 | 0.722 | 0.199 | 0.283 |
| IgG PF4/H (OD)† CLIA | 0.15 | 0.81 | 0.43 | 0.32 | 7.57 |
| SRA (%) | |||||
| Low-dose UFH | 97 | 31 | 53 | 80 | 74 |
| High-dose UFH | 15 | 1 | 4 | 0 | 0 |
| Platelet count nadir, ×109/L | 121 | 58 | 118 | 52 | 101 |
| Parenteral anticoagulant switch after stopping heparin | |||||
| Type, dose, and duration | IV danaparoid bolus 1000 U; then 300/h, 4 h, 150/h, 2 h; then VKA | IV argatroban 0.5 μg/kg/min, 10 d, then VKA | IV danaparoid bolus 2500 U; then, 300/h, 4 h; 150/h, 4 d, then fondaparinux | IV danaparoid bolus 2500 U; then 400/h, 4 h, 300/h, 4 h; 150/h, 17 d, then fondaparinux | None |
| Anticoagulant therapy | |||||
| Platelet count at anticoagulant introduction, ×109/L | 298 | 174 | 280 | 358 | — |
| Anticoagulant type, dose, duration | VKA, fluindione 10 mg, NA | VKA, warfarin 4 mg, long-term for AF | Fondaparinux, 7.5 mg, 90 d | Fondaparinux, 7.5 mg, 40 d, then factor Xa inhibitor, rivaroxaban 15 mg, long-term for active cancer | — |
| Follow-up after heparin discontinuation | |||||
| Time to platelet recovery, d | 3 | 6 | 2 | No recovery | 11 |
| Outcome events‡ | None | None | None | None | None |
| Time of last follow-up after anticoagulant introduction, mo | 0 | 5 | 2 | — | 14 |
| Patient no. . | 1 . | 2 . | 3 . | 4 . | 5 . |
|---|---|---|---|---|---|
| Age, y | 75 | 66 | 63 | 71 | 56 |
| Sex | M | F | M | F | M |
| BMI, kg/m2 | 37 | 30 | 23 | 25 | 28 |
| ECMO | No | No | No | No | No |
| Renal function | |||||
| CrCl, mL/min | 115 | 44 | 127 | 80 | 111 |
| Dialysis at the time of HIT diagnosis | No | Yes | No | No | No |
| Heparin therapy | |||||
| Indication | Heart valve surgery and AF | Heart valve surgery | Aortic thrombosis | DVT | Heart valve surgery |
| Type | UFH | UFH | UFH | UFH | UFH |
| HIT diagnosis | |||||
| 4Ts score | 5 | 6 | 5 | 7 | 4 |
| Delay since heparin initiation, d | 7 | 10 | 10 | 6 | 15 |
| HITT | None | Extension of preexisting thrombosis (jugular vein) + dialysis filter thrombosis | None | Extension of preexisting thrombosis | None |
| IgG PF4/H (OD)∗ ELISA | 1.513 | 1.145 | 0.722 | 0.199 | 0.283 |
| IgG PF4/H (OD)† CLIA | 0.15 | 0.81 | 0.43 | 0.32 | 7.57 |
| SRA (%) | |||||
| Low-dose UFH | 97 | 31 | 53 | 80 | 74 |
| High-dose UFH | 15 | 1 | 4 | 0 | 0 |
| Platelet count nadir, ×109/L | 121 | 58 | 118 | 52 | 101 |
| Parenteral anticoagulant switch after stopping heparin | |||||
| Type, dose, and duration | IV danaparoid bolus 1000 U; then 300/h, 4 h, 150/h, 2 h; then VKA | IV argatroban 0.5 μg/kg/min, 10 d, then VKA | IV danaparoid bolus 2500 U; then, 300/h, 4 h; 150/h, 4 d, then fondaparinux | IV danaparoid bolus 2500 U; then 400/h, 4 h, 300/h, 4 h; 150/h, 17 d, then fondaparinux | None |
| Anticoagulant therapy | |||||
| Platelet count at anticoagulant introduction, ×109/L | 298 | 174 | 280 | 358 | — |
| Anticoagulant type, dose, duration | VKA, fluindione 10 mg, NA | VKA, warfarin 4 mg, long-term for AF | Fondaparinux, 7.5 mg, 90 d | Fondaparinux, 7.5 mg, 40 d, then factor Xa inhibitor, rivaroxaban 15 mg, long-term for active cancer | — |
| Follow-up after heparin discontinuation | |||||
| Time to platelet recovery, d | 3 | 6 | 2 | No recovery | 11 |
| Outcome events‡ | None | None | None | None | None |
| Time of last follow-up after anticoagulant introduction, mo | 0 | 5 | 2 | — | 14 |
AF, atrial fibrillation; BMI, body mass index; CrCl, creatinine clearance evaluated with Cockcroft and Gault formula; DVT, deep vein thrombosis; ECMO, extracorporeal membrane oxygenation; F, female; HITT, heparin-induced thrombocytopenia-related thrombosis; M, male; NA, not available; VKA, vitamin K antagonist.
Positive threshold OD > 0.5.
Positive threshold OD > 1.
Thrombosis, major bleeding, clinically relevant nonmajor bleeding or death.