From the Guidelines
The cause of ulcers in a patient with essential thrombocytosis (ET) treated with hydroxyurea, who also received Fragmin (dalteparin) and Levofloxacin (levofloxacin), is most likely due to the combination of hydroxyurea's known side effect of mucocutaneous ulcerations and the potential exacerbation of bleeding risk by dalteparin. The patient's condition is complex, involving a prothrombotic state due to essential thrombocytosis, which can lead to microvascular occlusion and tissue ischemia, contributing to ulcer formation 1. Hydroxyurea, a common treatment for ET, is known to cause mucocutaneous ulcerations, particularly with long-term use, affecting approximately 10-15% of patients on this medication. The addition of dalteparin, a low molecular weight heparin, may increase the risk of bleeding, potentially worsening existing ulcers or contributing to their formation, as noted in the guidelines for its use 1. While levofloxacin is not directly ulcerogenic, it can delay wound healing through effects on connective tissue. Given the potential for these medications to contribute to ulcer formation, treatment should focus on wound care, careful monitoring of platelet counts, and consideration of alternative cytoreductive therapies if ulcers persist. Regular assessment of ulcer progression is essential to balance thrombosis prevention with minimizing medication side effects. In managing the patient's condition, it is crucial to weigh the benefits of these medications against their potential risks, particularly in the context of essential thrombocytosis, where the prothrombotic state already poses a risk for microvascular complications. The most recent guidelines, such as those from the National Comprehensive Cancer Network 1, should be consulted for the latest recommendations on managing ET and its complications. Ultimately, the goal is to minimize morbidity, mortality, and improve the quality of life for the patient, which may involve adjusting the treatment regimen based on the patient's response and the severity of side effects.
From the FDA Drug Label
5.5 Vasculitic Toxicities Cutaneous vasculitic toxicities, including vasculitic ulcerations and gangrene, have occurred in patients with myeloproliferative disorders during therapy with hydroxyurea. These vasculitic toxicities were reported most often in patients with a history of, or currently receiving, interferon therapy. If cutaneous vasculitic ulcers occur, institute treatment and discontinue hydroxyurea capsules.
The cause of ulcers in a patient with essential thrombocytosis (ET) treated with hydroxyurea is likely due to vasculitic toxicities, a known adverse reaction of hydroxyurea, particularly in patients with myeloproliferative disorders 2.
From the Research
Cause of Ulcers in ET Patients Treated with Hydroxyurea
The cause of ulcers in a patient with essential thrombocytosis (ET) treated with hydroxyurea can be attributed to the medication itself, as evidenced by several studies 3, 4, 5.
- Hydroxyurea is known to be effective in controlling thrombocytosis while reducing the risk of thrombosis in ET patients, but it may carry severe side-effects, including the development of painful leg ulcers 3.
- A study reported that 4% of ET patients treated with hydroxyurea developed painful leg ulcers, with most cases receiving over 1 gram of hydroxyurea per day for at least 1 year 3.
- Another study described three cases of ET patients who developed leg ulcers while taking hydroxyurea, with two cases showing complete healing of the ulcers after decreasing the dosage of hydroxyurea or switching to alternative treatments 5.
- The pathogenesis of hydroxyurea-induced skin ulcers remains unclear, but treatment is difficult and often requires prompt cessation of hydroxyurea therapy 3.
Role of Other Medications
The role of other medications, such as Fragmin (dalteparin) and Levofloxacin (levofloxacin), in the development of ulcers in ET patients treated with hydroxyurea is not directly addressed in the provided studies.
- However, it is essential to consider potential interactions between these medications and hydroxyurea, as well as their individual side-effect profiles, when evaluating the cause of ulcers in ET patients 6, 7.
- Further research is needed to determine the potential impact of these medications on the development of ulcers in ET patients treated with hydroxyurea.