Myelodysplastic syndrome (MDS)

Overview

Myelodysplastic syndrome (MDS) is a pre-malignant clonal disorder of haematopoietic stem cells characterized by ineffective blood cell production, abnormal blood cell development, and peripheral cytopenias.

It is primarily a disease of older adults and may progress to acute myeloid leukaemia (AML).

Pathophysiology

MDS results from abnormal development and function of haematopoietic stem cells leading to:

• Ineffective production of blood cells.

• Anaemia.

• Neutropenia.

• Thrombocytopenia.

• Increased risk of progression to AML.

Clinical presentation

Clinical features depend on the affected blood cell line.

Anaemia features

• Fatigue.

• Pallor.

• Reduced exercise tolerance.

• Shortness of breath.

Neutropenia features

• Recurrent infections.

• Fever.

Thrombocytopenia features

• Easy bruising.

• Bleeding tendency.

• Petechiae.

Investigations

Investigations are similar to aplastic anaemia and include:

• Full blood picture (FBP).

• Peripheral blood smear.

• Reticulocyte count.

• Bone marrow aspiration and trephine biopsy.

• Cytogenetic analysis.

• Analysis for 5q deletion.

Additional evaluation may include:

• Assessment of marrow blasts.

• Risk classification using appropriate prognostic scoring systems.

Management of Myelodysplastic syndrome (MDS)

Management depends on disease risk, symptoms, age, and overall clinical condition.

Supportive treatment

• Blood transfusion for symptomatic treatment.

AND

• Management of complications related to cytopenias.

Pharmacological treatment

• Azacitidine SC 75 mg/m² 24 hourly for 7 days, repeat every 28 days.

Azacitidine is a hypomethylating agent commonly used in higher-risk MDS and in patients who are not suitable candidates for intensive treatment or transplantation.

Treatment cycles are generally continued according to clinical response, tolerance, disease progression, or unacceptable toxicity.

Monitoring

Monitor:

• Full blood counts.

• Response to treatment.

• Treatment-related toxicity.

Complications

• Severe cytopenias.

• Recurrent infections.

• Bleeding complications.

• Progression to acute myeloid leukaemia (AML).

Referral

Refer patients to a specialist haematology centre for:

• Risk assessment.

• Bone marrow evaluation.

• Consideration of advanced treatment options.