The complex clinical picture of side effects to anticoagulation

Anticoagulation approach in morbid obesity: a comprehensive review on venous thromboembolism management

Obesity is a recognized risk factor for venous thromboembolism (VTE), associated with distinct challenges in managing anticoagulation therapy. There is still limited evidence regarding the impact of extreme body weight on the pharmacokinetics, pharmacodynamics, efficacy, and safety of various anticoagulant medications. To our knowledge, this is the first comprehensive review to address both prophylactic and therapeutic anticoagulant dosages specifically for managing VTE in patients with a body mass index (BMI) ≥40 kg/m2 or weight ≥120 kg. Our aim was to synthesize the findings of relevant studies alongside the latest recommendations on anticoagulation in this unique population. We gathered and analyzed data on all classes of anticoagulants available for VTE management, including vitamin K antagonists (VKAs), unfractionated heparin (UFH), low-molecular-weight heparin (LMWH), fondaparinux, and direct oral anticoagulants (DOACs), offering insights into their efficacy and safety profiles. Additionally, we explored special subpopulations of morbidly obese patients, such as those with cancer, renal dysfunction, or those undergoing bariatric surgery, recognizing the nuanced therapeutic challenges they present. The current evidence for anticoagulant therapy in morbidly obese patients with VTE is evidently insufficient, underscoring the need for a tailored approach and meticulous monitoring to achieve an optimal therapeutic balance.

Inflammatory and vaso-occlusive ulcers: Part I - Clinical presentation and diagnosis

In this CME, we review 2 specific categories of ulcers: inflammatory (where inflammation is the primary pathologic process leading to ulceration) and vaso-occlusive (where occlusion is the primary process). Inflammatory ulcers include pyoderma gangrenosum and vasculitides, whereas livedoid vasculopathy, calciphylaxis, and Martorell ulcers are vaso-occlusive ulcers. Determining the causes of ulcers in these conditions may require laboratory evaluation, biopsy, and imaging.

Approach to the Atypical Wound

The heterogeneity of atypical wounds can present diagnostic and therapeutic challenges; however, as the prevalence of atypical wounds grows worldwide, prompt and accurate management is increasingly an essential skill for dermatologists. Addressing the underlying cause of an atypical wound is critical for successful outcomes. An integrated approach with a focus on pain management and patient engagement is recommended to facilitate enduring wound closure. Advances in treatment, in addition to further research and clinical training, are necessary to address the expanding burden of atypical wounds.

Delayed-Type Heparin Allergy: Intravenous Tolerance Despite Inflammatory Skin Reaction After Subcutaneous Injection

BACKGROUND

Heparin allergy most frequently manifests as delayed-type hypersensitivity (DTH) causing an itchy inflammatory skin reaction at the site of subcutaneous injection. An important differential diagnosis is circumscribed skin necrosis due to heparin-induced thrombocytopenia.

OBJECTIVES

An inflammatory skin reaction to subcutaneously injected heparin generally entails the quest for alternative anticoagulation; concerns may particularly arise in an emergency situation requiring intravenous heparin administration.

METHODS

All heparin DTH cases seen in our department over the last 17 years underwent standardized allergy diagnostics including challenge testing, that is, subcutaneous injection of fondaparinux and intravenous administration of unfractionated heparin (UFH).

RESULTS

Of a total of 50 patients with confirmed heparin allergy, DTH was found in 48 (96.0%), and immediate-type, presumably IgE-mediated hypersensitivity was diagnosed in only 2 (4.0%). In the 48 DTH cases, intradermal testing revealed broad cross-reactivity between UFH and low-molecular-weight heparins (LMWH) including nadroparin, dalteparin, and enoxaparin. Cross-reactivity with (or concomitant sensitization to) fondaparinux was seen in only 3 (6.3%) cases. Intravenous administration of UFH was tolerated by all 45 patients challenged, despite DTH to UFH and LMWH as demonstrated by intradermal testing.

CONCLUSIONS

If an inflammatory skin reaction at the site of subcutaneously injected heparin is observed or reported without any evidence of skin necrosis or thrombocytopenia, intravenous administration of UFH seems to be sufficiently safe and may be considered without allergy testing if urgently indicated in an emergency situation. Fondaparinux is the most suitable alternative for subcutaneous application.

Safety of Direct Oral Anticoagulants in Central Nervous System Malignancies

Patients with brain tumors are at high risk for thromboembolic complications and frequently require anticoagulation. Direct oral anticoagulants (DOACs) are a less burdensome treatment for cancer-associated thrombosis with safety and efficacy comparable to those of low molecular weight heparin (LMWH); however, there are few data to support the use of DOACs in patients with brain tumors. The purpose of this study was to better understand the safety profile of anticoagulants in patients with primary and metastatic brain tumors, with particular interest in the safety and efficacy of DOACs. Our hypothesis was that DOACs are as safe and effective as LWMH in this population. This study was conducted through a single-center retrospective chart review of 125 patients with primary and metastatic brain tumors on anticoagulation. Our primary outcomes were major bleeding and intracranial hemorrhage (ICH), with secondary outcomes of minor bleeding and recurrent thrombosis. The rate of major bleeding was 26% in the LMWH group versus 9.6% in the DOAC group (p = .03). The rate of ICH was 15% in the LMWH group versus 5.8% in the DOAC group (p = .09). The severity of ICH in both groups was low with median Common Terminology Criteria for Adverse Events version 5 scores of 2 in the LMWH group and 3 in the DOAC group. The rates of minor bleeding and recurrent thrombosis were low in both groups. Our conclusion is that DOAC use in patients with brain tumors is not associated with increased rates of major bleeding compared with LMWH and is a safe and effective option. IMPLICATIONS FOR PRACTICE: Patients with brain tumors are at high risk for venous thromboembolism and frequently require anticoagulation. Direct oral anticoagulants (DOACs) are less burdensome than low molecular weight heparin (LMWH) for treatment of thromboembolism, but there is concern in the community over increased risk of bleeding. This study provides much-needed objective evidence that there are fewer major bleeding events in patients with brain tumors on DOACs compared to LMWH with similar efficacy. As the paradigm of anticoagulation in patients with cancer shifts from LWMH toward DOACs, this work is particularly meaningful as it suggests DOACs are safe and effective for patients with brain tumors.

Recurrent intradialytic heparin induced anaphylaxis: workup and management

Heparin has been widely used for intradialytic anticoagulation since the 1940s. Heparin induced anaphylaxis can be life threatening, mandating early recognition and intervention. However, due to its relative rarity many physicians remain unaware. We report the case of a 70-year-old woman requiring dialysis, who developed recurrent anaphylaxis to intradialytic heparin. We describe a systematic approach to confirm the suspected heparin allergy, which must include an evaluation of predisposing factors, the dialysis equipment and concomitant medications. Further workup for safe alternatives employing skin prick and intradermal tests, as well as provocation tests are discussed.

Allergic anaphylaxis due to subcutaneously injected heparin

Heparins are one of the most used class of anticoagulants in daily clinical practice. Despite their widespread application immune-mediated hypersensitivity reactions to heparins are rare. Among these, the delayed-type reactions to s.c. injected heparins are well-known usually presenting as circumscribed eczematous plaques at the injection sites. In contrast, potentially life-threatening systemic immediate-type anaphylactic reactions to heparins are extremely rare. Recently, some cases of non-allergic anaphylaxis could be attributed to undesirable heparin contaminants.

A 43-year-old patient developed severe anaphylaxis symptoms within 5–10 minutes after s.c. injection of enoxaparin. Titrated skin prick testing with wheal and flare responses up to an enoxaparin dilution of 1:10.000 indicated a probable allergic mechanism of the enoxaparin-induced anaphylaxis. The basophil activation test as an additional in-vitro test method was negative. Furthermore, skin prick testing showed rather broad cross-reactivity among different heparin preparations tested.

In the presented case, history, symptoms, and results of skin testing strongly suggested an IgE-mediated allergic hypersensitivity against different heparins. Therefore, as safe alternative anticoagulants the patient could receive beneath coumarins the hirudins or direct thrombin inhibitors. Because these compounds have a completely different molecular structure compared with the heparin-polysaccharides.

Livedoid vasculopathy: an intringuing cutaneous disease

Livedoid vasculopathy is a skin disease that occludes the blood vessels of the dermis. It has a pauciinflammatory or non-inflammatory nature. It is characterized by the presence of macular or papular, erythematous-purpuric lesions affecting the legs, especially the ankles and feet, and producing intensely painful ulcerations, which cause white atrophic scars called "atrophie blanche". This review includes studies and case reports found in the medical literature regarding the etiopathogenic associations of the disease, particularly those related to thrombophilia, their histopathological findings and the therapeutic approaches used in the difficult clinical management of these cases.

Adverse effects of heparin

All the adverse effects of heparins are related to their wide variety of biological activities, with bleeding being the most important safety issue, resulting directly from the potency of heparin as an anticoagulant. However, it is hard to define the bleeding risk, since it depends on numerous parameters including the indication, dosage, method, and duration of heparin application, the clinical study design and definition of bleeding as well as patient characteristics and determinants of bleeding such as type of surgery and co-medication. Nonbleeding complications of heparins are caused by binding of heparin molecules to proteins other than antithrombin and to cells, which is generally more pronounced with unfractionated heparin than with low-molecular-weight heparins. Accordingly, heparin-induced thrombocytopenia, the most severe nonbleeding adverse reaction, occurs about 10 times less with low-molecular-weight heparins than with unfractionated heparin. Frequent and therefore important adverse reactions of heparins are skin lesions resulting from delayed-type hypersensitivity reactions. All the other undesirable effects are discussed as well, but they are mostly clinically irrelevant.

Differential diagnosis and therapy of leg ulcers

A leg ulcer is a symptom and the treating physician needs to find out its origin by differential diagnostic approaches and procedures. The correct diagnosis leads to a specific therapy that ideally accelerates the healing of the ulceration. Identifying the pathogenesis of a leg ulcer is the first and main step towards healing. Although vascular diseases are the major causes of leg ulcers, one needs to consider, in addition to venous and arterial disorders, autoimmune, infectious, metabolic and neoplastic causes. The simple truth that one can only make a diagnosis that was considered holds particularly true in leg ulcers. The differential diagnostic considerations presented here appear in the daily routine of a dermatologist and the article provides help in diagnostic approaches and therapeutic decisions.