Subtle, persistent changes in energy, infections, or bruising can sometimes reflect what is happening inside the bone marrow, where blood cells are made. Myelodysplastic syndrome (often shortened to MDS) is a group of disorders that can lead to low blood counts over time, and its early symptoms are often easy to dismiss. Knowing the “silent signals” can help you recognize when routine bloodwork or a deeper evaluation may be worth discussing.

What is MDS and who is at risk?

Myelodysplastic syndrome refers to a set of conditions in which the bone marrow does not produce healthy, mature blood cells efficiently. Instead, it may make abnormal cells, too few functioning cells, or cells that die before they fully mature. The outcome is often persistently low blood counts (cytopenias) that can affect day-to-day well-being.

Risk tends to rise with age, and many diagnoses occur in older adults. Some people have an increased likelihood of developing MDS after certain cancer treatments such as chemotherapy or radiation, which can affect bone marrow stem cells. Long-term exposure to specific industrial chemicals (commonly discussed in relation to benzene) has also been associated with bone marrow disorders. In some cases, inherited or pre-existing bone marrow conditions can contribute, though many people diagnosed with MDS have no clear, identifiable cause.

MDS is not one single illness with one predictable course. Some forms progress slowly and are managed mainly by monitoring and supportive care, while others carry higher risk and may behave more aggressively. In certain cases, MDS can progress to acute myeloid leukemia (AML), but progression is not inevitable and depends on the MDS subtype and genetic findings.

What are the early warning signs of MDS?

The early warning signs of MDS often stem from shortages of normal blood cells.

Low red blood cells (anemia) can cause fatigue that feels out of proportion to your activities, shortness of breath with exertion, dizziness, palpitations, headaches, or reduced exercise tolerance. People may notice they need more rest, recover more slowly after activity, or feel unusually drained by routine tasks.

Low white blood cells (especially neutrophils) can increase susceptibility to infections. This may show up as infections that are more frequent than usual, take longer to resolve, or seem unusually severe. Recurrent sinus infections, skin infections, or repeated courses of antibiotics can be a clue, though many other conditions can cause the same pattern.

Low platelets can lead to easy bruising, frequent nosebleeds, bleeding gums, heavier menstrual bleeding, or pinpoint red/purple spots on the skin (petechiae). Cuts may bleed longer than expected. These symptoms do not prove MDS, but they are meaningful reasons to check a complete blood count (CBC), especially if they persist.

Why do these symptoms often go unnoticed?

Many MDS-related symptoms overlap with common, everyday explanations. Fatigue is frequently attributed to poor sleep, stress, depression, thyroid disorders, low iron, vitamin deficiencies, medication side effects, or heart and lung conditions. Mild shortness of breath may be chalked up to deconditioning or aging rather than a change in oxygen-carrying capacity.

Bruising can be explained away as bumping into objects, skin thinning with age, or the use of medications and supplements that affect bleeding. Frequent infections may be blamed on seasonal viruses, travel, workplace exposure, or contact with children.

Another reason these symptoms go unnoticed is the gradual pace at which blood counts can decline. People often adapt without realizing it: taking more breaks, avoiding stairs, or limiting activity. The body’s ability to compensate can delay recognition until counts drop further. Sometimes abnormal blood counts are first discovered incidentally during routine labs, before symptoms become obvious.

How does MDS affect your body’s blood production?

Healthy bone marrow acts like a factory, continuously producing red blood cells (carry oxygen), white blood cells (fight infection), and platelets (help blood clot). In MDS, this production process becomes inefficient. Blood-forming stem cells may develop changes that disrupt normal maturation, leading to poorly formed cells, early cell death within the marrow, and reduced release of healthy cells into the bloodstream.

This explains why MDS symptoms cluster into three main areas:

Anemia reduces oxygen delivery to tissues, contributing to fatigue, shortness of breath, lightheadedness, and reduced stamina.

Neutropenia weakens frontline immune defenses, increasing the chance of bacterial and some fungal infections.

Thrombocytopenia reduces clotting capacity, increasing bruising and bleeding.

Clinicians typically evaluate suspected MDS by repeating CBCs over time, reviewing a peripheral blood smear, and ruling out more common causes of low counts (for example, nutritional deficiencies such as vitamin B12 or folate deficiency). When abnormalities persist or are significant, a bone marrow biopsy is often needed to examine cell appearance (morphology), marrow cellularity, and chromosome or genetic changes. These results help classify the condition and estimate risk.

When should you seek medical attention?

Seek medical evaluation if symptoms are persistent, progressive, or affecting daily functioning, particularly if they cluster together (for example, ongoing fatigue plus frequent infections or easy bruising). In practical terms, consider contacting a clinician if fatigue lasts for weeks despite adequate rest, or if you notice new exertional shortness of breath, dizziness, or palpitations.

Prompt evaluation is also important for recurrent infections, fevers without a clear cause, or infections that feel unusually severe or slow to resolve. Bleeding-related symptoms warrant attention as well: frequent or unexplained bruises, repeated nosebleeds, gum bleeding, widespread petechiae, heavier-than-usual menstrual bleeding, or blood in urine or stool.

In the United States, primary care clinicians often start with a CBC and a review of medications, alcohol use, chronic illnesses, and nutrition-related labs that can mimic marrow disorders. If low blood counts are persistent or unexplained, referral to a hematologist is common. Urgent or emergency care is appropriate for chest pain, fainting, severe shortness of breath, uncontrolled bleeding, or fever in someone known to have low white blood cells.

MDS is not the most common explanation for these symptoms, but it is an important one to consider when blood counts are persistently abnormal or trending downward over time. Tracking symptoms, bringing prior lab results, and noting medication changes can help clinicians decide whether further testing is needed.

This article is for informational purposes only and should not be considered medical advice. Please consult a qualified healthcare professional for personalized guidance and treatment.