Myelodysplastic Syndromes (MDS) are a group of disorders where the bone marrow fails to produce sufficient numbers of healthy, mature blood cells. This bone marrow failure results in low counts of red cells, white cells, and/or platelets (cytopenia) in the bloodstream. Because the blood system affects the entire body, MDS often presents with symptoms beyond general fatigue, including noticeable changes in the skin. These dermatological issues can sometimes be the first physical indication of the underlying bone marrow dysfunction.
Skin Changes Due to Low Blood Counts
The most frequent skin manifestations in MDS are indirect consequences of the reduced number of functional blood cells (cytopenia). Anemia (low red blood cells) leads to a lack of oxygen-carrying capacity, manifesting externally as pallor. This paleness can be an early sign, though it may be less apparent in individuals with darker skin tones.
Thrombocytopenia (low platelets) directly impacts the body’s ability to clot blood, causing bleeding under the skin. This results in easy bruising (ecchymosis), even from minor pressure. Patients also frequently develop petechiae, which are tiny, pinpoint-sized red or purple dots representing minute hemorrhages. These petechiae often appear in areas of higher pressure and do not blanch when pressure is applied.
When neutrophils are low (neutropenia), the body’s defense against pathogens is compromised. This leaves the skin vulnerable to frequent infections, including cellulitis and abscesses. Compromised immune function can also slow the healing process of wounds, leading to chronic skin issues.
Inflammatory and Infiltrative Skin Disorders
MDS is also associated with specific, less common skin conditions driven by immune system abnormalities or the presence of malignant cells. These paraneoplastic syndromes relate to the bone marrow’s inability to regulate inflammation effectively. The most recognized is Sweet’s Syndrome (acute febrile neutrophilic dermatosis), which presents as the sudden onset of fever and tender, red-to-purple skin plaques.
Sweet’s Syndrome is a neutrophilic dermatosis, characterized by an abundance of neutrophils in the skin tissue without infection. Another severe neutrophilic dermatosis linked to MDS is Pyoderma Gangrenosum (PG). PG begins as small pustules or nodules that rapidly break down into painful, deep, non-healing ulcers with undermined, purple borders. The development of these inflammatory conditions may precede the MDS diagnosis in some cases.
Other immune-mediated reactions include Leukocytoclastic Vasculitis, where small blood vessels in the skin become inflamed. This presents as palpable purpura, which are raised, non-blanching red or purple spots, usually concentrated on the legs. A concerning manifestation is Leukemia Cutis, involving the direct infiltration of abnormal, immature myeloid cells into the skin. This infiltration signifies that malignant cells have moved outside the bone marrow and often signals progression toward aggressive leukemia.
Identifying and Treating Skin Symptoms
The evaluation of skin symptoms in a patient with MDS requires a comprehensive approach, starting with a review of complete blood count results. The presence of pallor, bruising, or petechiae prompts checking for anemia and thrombocytopenia, which are often managed with supportive measures. For any unusual rashes or lesions, an early skin biopsy is necessary to determine the underlying cause.
A biopsy allows pathologists to distinguish between hemorrhage, inflammation, and cellular infiltration, guiding the management strategy. Detecting a neutrophilic infiltrate indicates an inflammatory condition like Sweet’s Syndrome, while finding abnormal myeloid cells confirms Leukemia Cutis. Treatment for skin manifestations must address the underlying MDS, as the skin condition reflects the systemic disease.
Supportive care, such as transfusions of red blood cells or platelets, can alleviate symptoms related to cytopenias. Inflammatory conditions like Sweet’s Syndrome frequently require systemic therapy, often involving high-dose corticosteroids to reduce inflammation. Controlling the bone marrow disorder through disease-modifying agents or a stem cell transplant provides the most definitive resolution for MDS-related skin issues.