Refractory Heparin-Induced Thrombocytopenia With Cerebral Venous Sinus Thrombosis Treated With IVIg, Steroids, and a Combination of Anticoagulants: A Case Report

Inpatient Outcomes of Cerebral Venous Thrombosis in Patients With Malignancy Throughout the United States

BACKGROUND AND PURPOSE

Cerebral venous thrombosis (CVT) is associated with a high degree of morbidity and mortality. Our objective is to elucidate characteristics, treatments, and outcomes of patients with cancer and CVT (CA-CVT).

METHODS

The 2016-2019 National Inpatient Sample (NIS) database was queried for patients with a primary diagnosis of CVT. Patients with a currently active diagnosis of malignancy (CA-CVT) were then identified. Demographics and comorbidities were compared between CA-CVT and CVT patients. Subgroup analyses explored patients with hematopoietic cancer and non-hematopoietic cancers. Stroke severity and treatment were explored. Inpatient outcomes studied were discharge disposition, length of stay, and mortality.

RESULTS

Between 2016 and 2019, 6,140 patients had a primary diagnosis code of CVT, and 370 (6.0%) patients had a coexisting malignancy. The most common malignancy was hematopoietic (n=195, 52.7%), followed by central nervous system (n=40, 10.8%), respiratory (n=40, 10.8%), and breast (n=40, 10.8%). These patients tended to be older than non-CA-CVT and were more likely to have coexisting comorbidities. CA-CVT patients had higher severity scores on the International Study of Cerebral Vein and Dural Sinus Thrombosis Risk Score (ISCVT-RS) and increased complications. In a propensity-score matched cohort, there were no differences in inpatient outcomes.

CONCLUSION

Malignancy occurs in 6% of patients presenting with CVT and should be considered a potential comorbidity in instances where clear causes of hypercoagulabilty have not been identified. Malignancy was linked to higher mortality rates. Nonetheless, after adjusting for the severity of CVT, the outcomes for inpatients with cancer-associated CVT were comparable to those without cancer, indicating that the increased mortality associated with malignancy is probably due to more severe CVT conditions.

Early Utilization of Intravenous Immunoglobulin in Heparin-Induced Thrombocytopenia for Limb Salvaging Purposes

We present a case of a 28-year-old diabetic female who presented with high-burden lower extremity deep vein thrombosis (DVT) after previous exposure to unfractionated heparin (UFH). Heparin was discontinued, and non-heparin parenteral anticoagulant, argatroban, was started based on a high clinical suspicion of heparin-induced thrombocytopenia with thrombosis (HITT). The diagnosis of HIT was later proven by positive immune and functional assays. The severity of thrombocytopenia and the need for surgical intervention to salvage the limb prompted the use of intravenous immunoglobulin (IVIG) early on in the treatment course to recover platelet counts, halt the prothrombotic state, and prepare the patient for thrombectomy. The patient was put on direct oral anticoagulants (DOACs), apixaban, after thrombectomy, and platelet count recovery with no new thrombosis or bleeding episodes was reported after three months of follow-up.

Cerebral Venous Thrombosis in Patients With Heparin-Induced Thrombocytopenia a Systematic Review

BACKGROUND

Cerebral venous thrombosis (CVT) has recently been reported as a common thrombotic manifestation in association with vaccine-induced thrombotic thrombocytopenia, a syndrome that mimics heparin-induced thrombocytopenia (HIT) and occurs after vaccination with adenovirus-based SARS-CoV-2 vaccines. We aimed to systematically review the incidence, clinical features, and prognosis of CVT occurring in patients with HIT.

METHODS

The study protocol was registered with PROSPERO (CRD42021249652). MEDLINE, EMBASE and Cochrane CENTRAL were searched up to June 1, 2021 for HIT case series including >20 patients, or any report of HIT-related CVT. Demographic, neuroradiological, clinical, and mortality data were retrieved. Meta-analysis of proportions with random-effect modeling was used to derive rate of CVT in HIT and in-hospital mortality. Pooled estimates were compared with those for CVT without HIT and HIT without CVT, to determine differences in mortality.

RESULTS

From 19073 results, we selected 23 case series of HIT (n=1220) and 27 cases of HIT-related CVT (n=27, 71% female). CVT developed in 1.6% of 1220 patients with HIT (95% CI,1.0%-2.5%, I²=0%). Hemorrhagic brain lesions occurred in 81.8% of cases of HIT-related CVT and other concomitant thrombosis affecting other vascular territory was reported in 47.8% of cases. In-hospital mortality was 33.3%. HIT-related CVT carried a 29% absolute increase in mortality rate compared with historical CVT controls (33.3% versus 4.3%, P<0.001) and a 17.4% excess mortality compared with HIT without CVT (33.3% versus 15.9%, P=0.046).

CONCLUSIONS

CVT is a rare thrombotic manifestation in patients with HIT. HIT-related CVT has higher rates of intracerebral hemorrhage and a higher mortality risk, when compared with CVT in historical controls. The recently reported high frequency of CVT in patients with vaccine-induced thrombotic thrombocytopenia was not observed in HIT, suggesting that additional pathophysiological mechanisms besides anti-platelet factor-4 antibodies might be involved in vaccine-induced thrombotic thrombocytopenia-related CVT.

Refractory Heparin-Induced Thrombocytopenia in a Patient With Subarachnoid Hemorrhage-A Clinical Conundrum

Heparin induced thrombocytopenia (HIT) often resolves with discontinuation of heparin/ heparinoid products. Severe HIT with platelet counts <20,000/µL and disseminated intravascular coagulation is frequently associated with consumptive coagulopathy and systemic thrombosis. Management of severe HIT in patients who fail to improve on discontinuing heparinoid products and argatroban infusion is not well established. We describe a patient admitted with aneurysmal subarachnoid hemorrhage (SAH) who developed severe autoimmune HIT, failed conventional anticoagulation therapy with argatroban and progressed to develop extensive deep venous thrombosis and limb ischemia. She was successfully treated using bivalirudin, immunomodulation with 2 cycles of intravenous immunoglobulin and immunosuppression with methylprednisolone. Refractory severe HIT among SAH patients is rare and pose several therapeutic challenges. We report successful treatment using alternate anticoagulant and immune suppression and modulation.

Vaccine-induced thrombotic thrombocytopenia: the elusive link between thrombosis and adenovirus-based SARS-CoV-2 vaccines

The amazing effort of vaccination against COVID-19, with more than 2 billion vaccine doses administered all around the world as of 16 June 2021, has changed the history of this pandemic, drastically reducing the number of severe cases or deaths in countries were mass vaccination campaign have been carried out. However, the people's rising enthusiasm has been blunted in late February 2021 by the report of several cases of unusual thrombotic events in combination with thrombocytopenia after vaccination with ChAdOx1 nCov-19 (Vaxzevria), and a few months later also after Ad26.COV2. S vaccines. Of note, both products used an Adenovirus-based (AdV) platform to deliver the mRNA molecule - coding for the spike protein of SARS-CoV-2. A clinical entity characterized by cerebral and/or splanchnic vein thrombosis, often associated with multiple thromboses, with thrombocytopenia and bleeding, and sometimes disseminated intravascular coagulation (DIC), was soon recognized as a new syndrome, named vaccine-induced immune thrombotic thrombocytopenia (VITT) or thrombosis with thrombocytopenia syndrome (TTS). VITT was mainly observed in females under 55 years of age, between 4 and 16 days after receiving only Adenovirus-based vaccine and displayed a seriously high fatality rate. This prompted the Medicine Regulatory Agencies of various countries to enforce the pharmacovigilance programs, and to provide some advices to restrict the use of AdV-based vaccines to some age groups. This point-of view is aimed at providing a comprehensive review of epidemiological issues, pathogenetic hypothesis and treatment strategies of this rare but compelling syndrome, thus helping physicians to offer an up-to dated and evidence-based counseling to their often alarmed patients.

HIT in the head: a systematic review of cerebral venous sinus thrombosis in classical and autoimmune heparin-induced thrombocytopenia

Heparin-induced thrombocytopenia (HIT) causes thrombosis and thrombocytopenia, usually due to prior heparin exposure, so-called classical HIT. However, in the autoimmune form, the signs and symptoms of HIT occur without prior heparin exposure. Development of cerebral venous sinus thrombosis (CVST) secondary to HIT is a rare occurrence, with relatively few reports in the literature. There is a need to better understand the clinical presentation and treatment paradigms in these rare cases. Therefore, we present the first systematic review of CVST occurring in classical and autoimmune HIT. Cases of HIT-induced CVST were identified through a systematic search of Pubmed from the date of inception to March 2021. Literature search revealed 21 cases of HIT and associated CVST with six cases (28.6%) of autoimmune HIT. Patients presented with signs and symptoms consistent with increased intracranial pressure, intracerebral hemorrhage (ICH), and/or focal neurologic deficits. Headache was the most common symptom with 12 patients (60.0%) presenting as such. 10 patients (47.6%) included in the study developed ICH. Non-heparin anticoagulants, especially direct thrombin inhibitors, were the first-line treatment for the majority of patients (55.6%). Intravenous immunoglobulin (IVIG) was used as treatment for select patients (16.7%) with autoimmune HIT. Few patients received surgical intervention for CVST (14.3%) or ICH (30.0%). Four patients had a full recovery, four patients had residual deficits, and seven patients ultimately expired. Symptoms of HIT-induced CVST are often related to CNS dysfunction. Non-heparin anticoagulants are important to treat CVST, even when patients have concomitant ICH, and may be supplemented with IVIG if treating autoimmune HIT. Rapid identification and treatment of HIT-induced CVST is imperative in order to prevent morbidity and mortality.

Intravenous Immune Globulin (IVIG) for Treatment of Autoimmune Heparin-Induced Thrombocytopenia: A Systematic Review

OBJECTIVE

To evaluate intravenous immune globulin (IVIG) for autoimmune heparin-induced thrombocytopenia (aHIT), including platelet recovery, IVIG dose, dosing weight, IVIG product used, and complications reported.

DATA SOURCES

PubMed and EMBASE were searched from inception through June 21, 2020. Search terms included heparin-induced thrombocytopenia, HIT, intravenous immune globulin, IVIG, autoimmune HIT, aHIT, and immune globulin.

STUDY SELECTION AND DATA EXTRACTION

Patients administered IVIG for HIT and diagnosed by immunoassay (optical density ≥2) or positive activation assay were included.

DATA SYNTHESIS

Twenty-four cases were reviewed; 92% had persistent aHIT. Time to IVIG administration post-nonheparin anticoagulant initiation was 9 days (median). Most common IVIG cumulative dose was 2 g/kg (dosed as 1 g/kg/d for 2 consecutive days); 75% had a favorable platelet increase (≥50 × 10⁹/L) within 5 days of initial IVIG dosing.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

aHIT is characterized by critically low platelets, thrombosis, and a persistent delay in platelet recovery despite treatment with a nonheparin anticoagulant. An immunoassay and subsequent confirmatory activation assay (at low, high, and 0 IU/mL unfractionated heparin levels) is recommended to confirm diagnosis. Patients nonresponsive to nonheparin anticoagulants within 5 days of initiation should be evaluated for IVIG treatment (2 g/kg cumulative dose). More data are needed to clarify appropriate IVIG dosing weight, although based on current published literature, it is recommended to use actual body weight.

CONCLUSIONS

Data reported support use of IVIG as adjunctive therapy for patients with aHIT. Judicious IVIG use based on key clinical and laboratory findings is critical.