Table 1 Clinical symptoms, laboratory and radiological findings and treatment in an illustrative case of ITPR1-IgG-positive encephalitis over a period of 2 years
Aug–Sep 19 | End Oct 19 | Mid-Jan 20 | Feb 20 | Mar 20 | End Mar 20 | Beg-May 20 | Jul 20 | Sep 20 | Oct 20 | Nov 20 | Jan 21 | Apr 21 | Jun 21 | Mid-Jul 21 | Aug 21 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Clinical course | 1st symptoms Aug 19 (incr. forgetfulness), rapid decline in short-term memory, confused actions, personal. changes Sep 19 | Hosp. admiss.: dysdiad..; flat affect, irritab., persever., sev. cogn. impairm. (conc./attent.; short + long-term + working mem., process. speed, action plann., probl./error recogn.)→ “dysexec. dementia” → rapid deteror. with disor., impair. impulse contr., behav. abnorm | Sust. marked improvem. (normal. affect and exec. funct. with restored probl. recogn. + solution capac.) but mild resid. attent. deficit | Relapse with marked decline in cognitive function (see Appendix for details) | Marked improvem. of impulse contr., reduct. in psychomot. restlessn., but resid. impair. attent. + proc. speed | Newly emerging ataxia and mild tetraparesis | 1st dose of CYCL→ further im- prov. of cogn. test results, but residually impaired attent., mem., and proc. speed | - | - | Relapse-like epis. ~ 1 mo after 3rd CYCL cycle, attent. + mem. defic., disorient., psychomot. restlessn. and formal thought disorder | Signific. neurocogn. improvem., compl. psychiatr. recovery Nov 20; followed by relat. stability Dec 20-Aug 21, but mild increase in symptom severity shortly before each CYCL cycle; episode of blurred vision in both eyes June 21 (lasting for 6–8 weeks, followed by complete recov.); re-admitted mid-Jul 21 with mild depress. disorder plus mild subj. decline in short-term mem. and exec. functions (prompt resolution after IVMP) | At last follow-up: resid. cogn.def.; gait instab. and limb ataxia mostly resolved but still uses rollator for resid. parapar | ||||
ITPR1-IgG CBA, serum | – | 1:1000 | 1:1000 | 1:1000 | – | – | 1:100 | – | – | – | 1:320 | – | – | – | – | 1:1000 |
ITPR1-IgG CBA, CSF | – | 1:1 | – | 1:4 | – | – | – | – | – | – | – | – | – | – | – | – |
ITPR1-IgG CBA, PLEX-E | – | – | 1:320 | – | – | – | – | – | – | – | – | – | ||||
ITPR1-IgG TBA, serum | - | 1:320 | 1:1000 | – | – | – | – | – | – | – | – | – | – | – | – | – |
Other anti-neural Abs | – | Neg | Neg (serum + CSF) | Neg | – | – | – | – | – | – | – | – | – | – | – | – |
CTD-ass. auto-Abs | – | Neg | – | Neg | – | – | – | – | – | – | – | – | – | – | – | – |
CSF | – | Normal | Normal | Normal | – | – | – | – | – | – | – | – | – | – | QAlb ↑ | – |
CRP (mg/l; < 5) | – | 7 → 7.7 → 9.3 | 13 | Normal | – | – | – | – | – | 13 | – | – | – | – | – | – |
BSR (mm/h; < 20) | – | 22 | – | Normal | – | – | – | – | – | – | – | – | – | – | – | – |
CA125 (U/ml; < 35) | – | – | 111 | 88 | – | – | – | – | – | – | – | – | – | – | – | 35 |
MMSE | – | 27/30 → 23/30 → 29/30 at discharge end of Nov | 29/30 | 24/30 | 28/30 | – | 30/30 | – | – | – | – | – | – | – | – | – |
Clock-drawing test | – | 3/7 | 7/7 | 1/7 | 3/7 | – | 7/7 | – | – | – | – | – | – | – | – | – |
DemTect | – | 9/18 | 16/18 | 8/16 | 14/18 | – | 15/18 | – | – | – | – | – | – | – | – | – |
EEG | – | 2 × ri frontopar. delta activ | Ri par.-occ. theta activ | Ri par.-occ. theta activ | Normal | – | – | – | – | Intermittent ri-temp. slowing | Normal | – | – | – | – | – |
cMRI | – | 2 × normal (1 × with Gd) | Normal | Normal | - | – | – | – | – | Normal | – | – | – | – | Normal | – |
sMRI | – | – | – | Normal | - | – | – | – | – | - | – | – | – | – | – | – |
FDG-PET, head | – | – | – | Glucose metabol. ↑ ri med. temp lobe (amygd., parahipp.) + ri striatum, esp. putamen | - | – | – | – | – | - | – | – | – | – | – | – |
FDG-PET, body | – | – | – | Normal | - | – | – | – | – | - | – | – | – | – | – | – |
CT abd/thor/pelv | – | Bilat. small nodular abnormal. in the lung (< 6 mm), cystic structures at isthmus uteri | - | Normal (pelv.) | - | – | – | – | – | - | – | – | – | – | – | – |
Acute treatment | IVMP (5 × 1 g) | IVMP (3 × 1 g)a, oral tapering | IVMP (5 × 1 g), 5 × PLEX, IVIG (4 × 35 g/day) | – | – | – | – | – | IVMP (5 × 1 g)b, oral tapering | – | – | – | – | IVMP (3 × 1 g) | – | |
Outcome from acute therapy | – | Almost complete resolution | Substantial improvement | Significant improvement | – | – | – | – | – | Significant improvement | – | – | – | – | Prompt resolution | – |
Cyclophosphamide | – | – | – | – | – | – | CYCL (350 mg/ m2/d for 3 d) | CYCL | CYCL | - | CYCL | CYCL | CYCL | CYCL | - | CYCL |