Video 1.
This Video Shows Patient 1 after the Treatment. The examination was performed at age 25, 4 years after the onset of ataxia. At that time, she was on prednisone 5 mg every other day. She had only very mildly slurred and scanning speech. Eye movement examination revealed no square wave jerks. There was no limitation of eye movements in any direction on both smooth pursuit and saccade examination. There were no apparent saccadic or broken pursuits. There was mild left beating gaze-evoked nystagmus on the extreme left gaze. Saccades were normal. There was neither slowing of saccades nor hypermetric saccade. Mild dysmetria and overshoot dysmetria, left greater than right, were demonstrated on finger-to-nose-to-finger and finger following tests, respectively. There was mild dysdiadochokinesia, which was more prominent on the left. She was able to walk independently, but her gait was wide-based. She had imbalance when standing with both feet together and eyes closed. She required assistance when standing on only one foot, either left or right.
Video 2.
This Video Shows Patient 2 after the Treatment. The examination was performed at age 40, 2 years after the onset of ataxia. She was on azathioprine 150 mg/day and a tapering dose of oral prednisone. The cerebellar features in this patient were overall more prominent than in patient 1. Her speech was moderately slurred and scanning. Eye movement examination demonstrated mild square wave jerks. Pursuits were normal. There were hypermetric saccades, more prominent in horizontal than vertical directions. There was no slowing of saccades or limitation of eye movements in any direction. Mild dystonic posturing of both hands, right slightly greater than left, was demonstrated. Finger-to-nose-to-finger test revealed mild dysmetria, left greater than right. Finger following test demonstrated mild-to-moderate overshoot dysmetria, left greater than right. Mild-to-moderate dysdiadochokinesia, left greater than right, was also demonstrated. She was able to walk independently, but had wide-based gait. She was unable to stand with both feet together without assistance, and had marked difficulty standing on only one foot.
Table 1.
Our Cases and Previously Reported Cases of Steroid-responsive Encephalopathy Associated with Autoimmune Thyroiditis (SREAT) with Pure or Predominant Cerebellar ataxia.
| Authors/Year | Age (yr) | Sex | Phenomenology of Ataxia | Other Neurologic Features | Time to Dx (mo) | Thyroid status | Anti-TPO | Ant-Tg | Treatment | Outcome of Ataxia |
|---|---|---|---|---|---|---|---|---|---|---|
| Patient 1 | 21 | F | Limb, trunk, gait | None | 3 | Eu | 1:1600 (1:100) | 1:40 (1:20) | IVMP → PO Pred | Improved markedly with residual plateaued mild ataxia |
| Patient 2 | 40 | F | Limb, gait | Dystonia – b/l hands | 6 | Eu | 238.87 IU/mL (0–5.61) | 57.35 IU/mL (0–4.11) | IVMP → AZA | Moderately improved, then plateaued over 2-yr follow-up period |
| Alvarez Bravo et al.13 | 47 | F | Limb, trunk, gait | Opsoclonus | 0.5 | Eu | 765 IU/mL (<34) | nl | IVMP → PO Pred | Excellent |
| Alzuabi et al.14 | 17 | F | Limb, gait, nystagmus, intention tremor | Vestibular - vertigo, nausea, vomiting; Optic neuritis, L>R | 2 | Hypo (subclinical) | 423 IU/mL (at the first f/u) | 62.9 IU/mL | IVMP → MMF | Markedly improved → 2 relapses (4 and 20 mo later); also had similar symptoms 1 yr prior to this Dx |
| Lee et al.15 | 30 | M | Limb | Ocular flutter | 0.13 | Eu | nl | 398 U/mL (<115) | IVMP → PO Pred | Excellent (full recovery 3 mo after) |
| Matsunaga et al.16 (Pt 4) | 63 | F | Limb, trunk | "Tremor" | 1 | Eu | 28.1 U/mL (<0.3) | 316 U/mL (<0.3) | IVMP | Excellent (full recovery) |
| Matsunaga et al.16 (Pt 5) | 66 | F | Limb, trunk, dysarthria | "Tremor" | 2 | Eu | 105 U/mL (<0.3) | 255 U/mL (<0.3) | IVMP | Good |
| Matsunaga et al.16 (Pt 7) | 84 | F | Limb, trunk, dysarthria | None | 72 | Eu | 14.8 U/mL (<0.3) | 2.7 U/mL (<0.3) | IVMP | Fair |
| Matsunaga et al.16 (Pt 8) | 55 | M | Limb, trunk, dysarthria | None | 4 | Eu | 7.7 U/mL (<0.3) | <0.3 U/mL (<0.3) | IVMP | Fair |
| Matsunaga et al.16 (Pt 10) | 54 | M | Limb, trunk, dysarthria | None | 120 | Eu | 0.5 U/mL (<0.3) | 10 U/mL (<0.3) | IVMP | Good |
| Matsunaga et al.16 (Pt 11) | 61 | M | Limb, trunk, dysarthria | None | 12 | Eu | 59.7 U/mL (<0.3) | 5.1 U/mL (<0.3) | IVMP, IVIG | Good |
| Matsunaga et al.16 (Pt 12) | 57 | F | Limb, trunk | None | 12 | Eu | 109 U/mL (<0.3) | 1.6 U/mL (<0.3) | IVMP | Fair |
| Matsunaga et al.16 (Pt 13) | 46 | F | Limb, trunk | "Tremor" | 6 | Eu | 1.9 U/mL (<0.3) | <0.3 U/mL (<0.3) | IVMP | Fair |
| Tang et al.19 | 39 | M | Limb, gait, dysarthria | Facial, b/l arm weakness (gr 4/5) | 17 | Eu | >1,300 U/mL (0–60) | 83.2 U/mL (0–60) | IVMP → PO Pred | Able to walk 1,000 m along but speech was unchanged |
| Nakagawa et al.17 | 41 | F | Gait, limb, mild dysarthria | None | 9 | Eu | 50 U/mL (<0.3) | 4.9 U/mL (<0.3) | IVMP → PO Pred | Ataxia almost disappeared at 3-mo follow up |
| Avila et al.28 | 72 | F | Gait | Myoclonus at b/l arms; impaired verbal memory, attention and mild frontal syndrome on cognitive testing | 18 | Hypo (subclinical) | >453 IU/mL (<18) | >4,262 IU/mL (<28) | Steroids | Dramatic but temporary improvement; Died 6 wk later |
| Selim and Drachman18 (Pt 1) | 57 | F | Gait, hands, dysarthria, nystagmus | “Dizziness”, diplopia peripheral neuropathy | “Long-standing” | Eu | >30 IU/mL (0.3–1) | 2.9 IU/mL (0.3–1) | L-thyroxine | Continued to deteriorate; able to ambulate with only a walker 6 yr after |
| Selim and Drachman18 (Pt 2) | 35 | F | Gait, hands, dysarthria | None | 60 | Eu | 13.2 IU/mL (0.3–1) | 1.7 IU/mL (0.3–1) | L-thyroxine | No improvement; worsening gait disability 3 yr later |
| Selim and Drachman18 (Pt 3) | 56 | F | Gait, hands, dysarthria | Vertigo | 72 | Eu | 22.1 IU/mL (0.3–1) | 16.9 IU/mL (0.3–1) | PO Pred (then stopped due to hypertension) | Continued to deteriorate; became wheelchair bound |
| Selim and Drachman18 (Pt 4) | 69 | F | Gait, hands, dysarthria | Diplopia, extrapyramidal features (at onset); lapses in concentration on cognitive testing | N/A | Eu | 3.7 IU/mL (0.3–1) | 1.8 IU/mL (0.3–1) | L-dopa | Continued to deteriorate |
| Selim and Drachman18 (Pt 5) | 46 | F | Gait, hands, dysarthria, nystagmus | Diplopia, vertigo, hearing impairment, peripheral neuropathy | 3 | Eu | 2 IU/mL (0.3–1) | 1.5 IU/mL (0.3–1) | IVIG (given 8 mo after the initial evaluation) | Able to ambulate with walker 2 mo after IVIG but other features are unchanged |
| Selim and Drachman18 (Pt 6) | 61 | M | Gait, hands, dysarthria | Hearing impairment, extrapyramidal features | 60 | Eu | 82.7 IU/mL (<35) | <20 IU/mL (<35) | N/A | N/A |
[i] Abbreviations: Ant-Tg, Anti-thyroglobulin; Anti-TPO, Anti-thyroid peroxidase; AZA, Azathioprine; b/l, Bilateral; Dx, Diagnosis; Eu, Euthyroid; F, Female; gr, Grade; Hypo, Hypothyroidism; IU/mL, International Units per Milliliter; IVIG, Intravenous Immunoglobulin; IVMP, Intravenous Methylprednisolone; M, Male; m, Meter; MMF, Mycophenolate mofetil; mo, month(s); N/A, Not Applicable; nl, Normal; PO Pred, Oral Prednisone; Pt, Patient; U/mL, Units per Milliliter; wk, Week(s); yr, Year(s). The patients were reported in chronological order of year of publication. Of note, the numbers of patients in the original reports are indicated in parentheses. Age at the time of diagnosis, sex, phenomenology of ataxia, other neurologic features, time to the diagnosis of SREAT (in months), serum anti-TPO, anti-Tg with normal values in parentheses, treatment and outcomes of ataxia after treatment are demonstrated. Note that normal values of anti-TPO and anti-Tg antibodies are different between laboratories.