Can dialysis cause thrombocytopenia (low platelet count)?

From the Guidelines

Dialysis can cause thrombocytopenia due to various mechanisms, including mechanical consumption of platelets, heparin-induced thrombocytopenia, and the effects of uremic toxins on platelet production and function. The study by 1 highlights the significant blood losses associated with dialysis, including occult gut bleeding, which can contribute to thrombocytopenia. According to the study, hemodialysis patients can lose up to 2.2 L of blood per year due to occult gut bleeding, which can lead to a decrease in platelet count.

Some of the key mechanisms by which dialysis can cause thrombocytopenia include:

• Mechanical consumption of platelets during dialysis, as platelets can adhere to the dialysis membrane
• Heparin-induced thrombocytopenia (HIT), a serious immune-mediated reaction caused by the use of heparin as an anticoagulant during dialysis
• Effects of uremic toxins on platelet production and function, which can lead to a decrease in platelet count
• Underlying kidney disease, which can also contribute to thrombocytopenia

As noted in the study by 1, the use of anticoagulants, such as heparin, can increase the risk of thrombocytopenia in dialysis patients. The study also highlights the importance of monitoring blood losses in dialysis patients, including occult gut bleeding, to prevent and manage thrombocytopenia. Regular monitoring of platelet counts and management of contributing factors, such as switching to alternative anticoagulants or changing the dialysis membrane type, are crucial to preventing and treating thrombocytopenia in dialysis patients.

From the Research

Dialysis and Thrombocytopenia

• Thrombocytopenia, or low platelet count, is a potential complication of dialysis therapy, with studies suggesting that it can occur due to various factors related to the dialysis process 2, 3, 4, 5.
• The drop in platelet count during dialysis sessions can be attributed to platelet adhesion and complement activation, regardless of the membrane material used in the dialyzer 2.
• Research indicates that the platelet count can decrease by up to 15% during a hemodialysis session, with recovery after the end of treatment 2.
• Several case reports have described patients who developed thrombocytopenia during dialysis, with investigations revealing that the condition was likely caused by the dialysis treatment itself, rather than other underlying factors 3, 4.

Causes and Mechanisms

• The exact mechanisms of dialysis-related thrombocytopenia are not fully understood, but it is thought to involve platelet activation and aggregation secondary to exposure to the dialyzer membrane or other factors related to the dialysis process 2, 3.
• Heparin-induced thrombocytopenia (HIT) is a specific type of thrombocytopenia that can occur in patients exposed to heparin during dialysis, with a reported incidence of up to 12% in dialysis patients 6.
• Other potential causes of thrombocytopenia in dialysis patients include underlying patient-related factors, such as platelet dysfunction or hematological diseases, as well as specific dialysis-related factors, such as the type of dialyzer membrane or sterilization method used 4, 5.

Diagnosis and Management

• Thrombocytopenia in dialysis patients can be challenging to diagnose and manage, with a systematic approach to evaluation and treatment recommended 4, 5.
• Laboratory tests, including platelet count and heparin-induced thrombocytopenia testing, can help diagnose thrombocytopenia and identify potential causes 3, 6.
• Management of thrombocytopenia in dialysis patients may involve adjusting the dialysis treatment, such as changing the dialyzer membrane or sterilization method, or using alternative anticoagulation strategies, such as citrate anticoagulation or heparin-free dialysis 2, 6.