SREAT Relapse vs. Steroid Withdrawal: Warning Signs

Tapering off corticosteroids after being treated for Steroid-Responsive Encephalopathy Associated with Autoimmune Thyroiditis (SREAT, also known as Hashimoto’s encephalopathy) can be a highly anxious time. Relapses have been reported during dose reductions and after stopping medications, though their exact frequency and timing are uncertain ^[1][2].

Because tapering steroids also causes a predictable withdrawal process, it can be very difficult to know if your body is just adjusting to lower medication levels, if your adrenal glands are struggling, or if SREAT is returning. It is crucial to understand that you cannot reliably diagnose the cause of your symptoms at home. While withdrawal often causes physical fatigue and SREAT often causes neurological issues, these conditions overlap significantly. For example, a relapse might begin with generalized fatigue, while withdrawal or adrenal insufficiency can cause confusion, sleep disturbances, and mood changes ^[3][4][5]. Always seek a clinician’s assessment for new or worsening symptoms rather than trying to diagnose yourself based on how a symptom feels.

🚨 EMERGENCY RED FLAGS

Do not wait for a doctor’s appointment, a scheduled test, or a callback if you experience any of the following. Call emergency services immediately. These can be signs of a life-threatening adrenal crisis, a severe SREAT relapse, an infection, or another medical emergency like a stroke:

• Neurological emergencies: First or prolonged seizures, sudden inability to speak or walk, markedly reduced consciousness, coma, or rapidly worsening confusion ^[3][6].
• Psychiatric emergencies: New severe psychosis, delusions, or hallucinations ^[3].
• Adrenal Crisis signs: Collapse, fainting (syncope), severe dizziness upon standing (hypotension), persistent vomiting, inability to keep steroid medication down, or severe physical weakness ^[7][5].

Potential Signs of a SREAT Relapse

A SREAT relapse means the encephalopathy (brain dysfunction) has returned. During a steroid reduction, relapses often—but not always—mimic the exact symptoms you experienced during your initial episode ^[2][1]. Features that raise clinical concern for a relapse include:

• Cognitive and Neurological Deficits: Severe memory impairment, confusion, clumsiness or loss of balance (gait disturbance), speech problems, and involuntary movements ^[3][2].
• Psychiatric Changes: Profound mood swings, major behavioral changes, or persecutory delusions (beliefs that someone is trying to harm you) ^[3]. (Note: Corticosteroids themselves, as well as adrenal issues, can also cause significant psychiatric side effects, meaning any severe mood or behavioral change requires formal medical evaluation).

Glucocorticoid Withdrawal and Adrenal Insufficiency

When you take high doses of steroids for a prolonged period, your body’s adrenal glands suppress their natural production of cortisol. As you taper, it takes time for this system to recover ^[8].

• Glucocorticoid Withdrawal Syndrome: This common adjustment period often causes profound generalized fatigue, muscle aches (myalgias), joint pains (arthralgias), sleep disturbances, and mild to moderate mood changes ^[4][9].
• Adrenal Insufficiency: If your adrenal glands do not wake up adequately, you may develop adrenal insufficiency. This can happen gradually, causing increasing fatigue, nausea, and weakness. If severe, it can culminate in a sudden, life-threatening adrenal crisis ^[7][5].

Why Diagnosis Requires Your Doctor

There is no single confirmatory test for a SREAT relapse, and your care team will need to evaluate you to rule out other causes like infections, medication side effects, or metabolic imbalances ^[10].

• Scans and tests can be normal: Having a normal brain MRI or normal routine cerebrospinal fluid (CSF) results does not exclude a relapse ^[2]. An EEG (brain wave test) is often abnormal in SREAT (typically showing generalized slowing), but this finding is nonspecific and cannot definitively prove a relapse on its own ^[3].
• Antibodies are not proof of relapse: High thyroid antibodies are common in autoimmune thyroid disease but do not measure current brain inflammation. In one study of patients referred for suspected Hashimoto’s encephalopathy who had elevated thyroid antibodies, 73% were ultimately found to have a completely different, non-immune diagnosis ^[11].
• Adrenal testing: Your doctor may use tests like a morning cortisol draw or an ACTH stimulation test to check if your adrenal glands are recovering ^[12].

Your Action Plan

• Follow your taper strictly: Do not speed up, stop, or change your long-term steroid taper without your prescriber’s direction.
• Use sick-day rules if prescribed: If your doctor has given you a specific “sick-day plan” (instructions to take extra steroids during a fever, major illness, or vomiting) or an emergency hydrocortisone injection kit, follow those instructions and seek immediate medical care.
• Track your symptoms: Keep a daily symptom diary noting your current dose, the timing of symptoms relative to dose reductions, sleep patterns, and any physical or neurological changes. This gives your care team objective data to review.