Transcript A case of somnolence after shingles

Varicella-zoster encephalitis – a
case history
Southern Neurology
Case history
H.J.
 63 y.o.male
 Presents August ’03 with 2 week history of somnolence,
poor concentration, increasing generalised weakness,
intermittent headaches, nausea and visual hallucinations
 1 week prior to onset of symptoms had right T1 HZ
infection. Given valacyclovir but ceased after 2 days due
to nausea

Past medical history
Diabetes mellitus since age 40 years. Insulin requiring > 5
years. Diabetic nephropathy – proteinuria 0.18 g/day;
serum creatinine May ’03 of 140.
 Chronic inflammatory demyelinating polyneuropathy ~ 5
years. Treated with IV immunoglobulin and for past 6
months mycophenylate.
 IHD – AMI and CABGs 10 years ago
 Hypertension
 Dyslipidaemia

Medications
Mixtard 30/70 70 U mane; protaphane 40 U nocte
 Lopid 600 mg bd
 Lasix 125 mg mane; Aldactone 25 mg bd
 Captopril 25 mg bd
 Magnesium 500 mg nocte
 Transiderm nitro patch
 Solprin 75 mg mane
 Nexium 40 mg mane

Clinical examination
 Afebrile
but dehydrated and hypotensive
 Somnolent (± drowsy) and but easily roused
 Orientated to time, place and person
 HS dual, no murmurs; chest clear
 Signs of peripheral neuropathy with distal
weakness grade 3-4/5 upper and lower limbs,
areflexia and distal glove and stocking sensory loss
Initial investigations
 WCC
9.6, Hb 103, Plat 310
 Na 132, K 5.2, Urea 40, Creat 309
 HbA1c 8.8%
 CXR clear
 ECG SR, no ischaemic changes
 MSU no growth
 CT brain normal
Differential diagnosis
?
Diagnosis
?
Further investigations
Further investigations and treatment
Lumbar puncture – successful after several attempts
(patient weighed 120 kg). CSF protein 0.54, Glc 3.0, cell
count 90 lymphocytes, 2 polymorphs, 1 RBC.
 Commenced IV acyclovir initially 1 g bd but changed
subsequently to 750 mg tds.
 Lasix, aldactone, captopril and dilatrend all temporarily
ceased.
 Mycophenylate withdrawn
 CSF Varicella-Zoster PCR positive

Clinical progress
Improved dramatically within 72 hours.
 Treated with IV acyclovir for 10 days followed by oral
valacyclovir 1 g tds for 14 days.
 Discharged home at day 10.
 Readmitted Nov’03 with 1 week history of increasing
somnolence, confusion, hallucinations. Clinically
dehydrated, serum urea 28, creatinine 239.
 CT brain normal
 Rpt LP < 1 WBC, CSF protein 0.43, Glc 5.1, VZ PCR neg
 Improved with rehydration and sent home

Varicella-zoster: a re-emerging
infection
 A recent
Finnish study (J Neurovirol 2001; 7: 4008), using PCR to detect various viruses in the CSF
of over 3000 patients who had CNS infections
including encephalitis, meningitis and myelitis
,found that VZ virus was the most frequently
detected at 29% with HSV and enetroviruses
accounting for 11% of cases each, and influenza A
virus found in 7% of cases.
VZ virus reactivation in the CNS/PNS
Latent in cranial nerve and dorsal root ganglia.
 CNS - myelitis, large vessel encephalitis/granulomatous
arteritis, small vessel encephalitis, menigo-encephalitis
and ventriculitis.
 PNS - herpes zoster ± post-herpetic neuralgia, cranial
mononeuropathy (eg Bell’s palsy) or polyneuropathy,
post-infectious generalised polyneuritis (GBS).
 All may occur with or without cutaneous manifestations.

Reactivation: zoster (shingles,
ganglionitis)
In U.S.A., 300,000-850,000 cases per year.
 8-10 fold increased frequency in ages > 60 years
compared to < 60 years
 Incidence of recurrent zoster < 5%
 Thoracic zoster most common followed by lesion of the
face, most often opthalmic division of trigeminal nerve.
Zoster oticus and peripheral facial weakness constitutes
Ramsay-Hunt syndrome.
 Zoster cranial neuropathy may develop weeks after acute
infection due to slow spread along afferent fibres to small
vessels

VZ encephalitis in immuno-compromised
patients (Neurology 1999; 52: 193-95)
Two patients with AIDS and one with HD who developed
headache in 2 patients, seizures in 2 patients, and
hemiparesis and myelopathy in 1 patient. The two AIDS
patients had HZ 4-8 months prior and the HD patient had
no history of cutaneous zoster.
 Initial CTs normal but MRIs showed well defined
spherical, nonenhancing subcortical lesions with
progression to coalescence, cavitation, haemorrhage and
enhancement.
 Histologically, demyelination, necrosis, with
accompanying astrogliosis and macrophage infiltration.

(A) Unenhanced T1-weighted MR image shows gyral hemorrhage and clusters of
spherical hypointense lesions along the right frontoparietal cortical and subcortical areas.
(B) Enhanced T1-weighted MR image shows homogeneous and ring-enhancing lesions.
(C) Proton density MR image reveals spherical and clustered hyperintense lesions.
Additional lesions are seen in the right frontal subcortical white matter that are not
evident on the T1-weighted images
Focal cavitation in the digitate white matter and graywhite junction. Note the spherical lesions in the
adjacent subcortical white matter. These lesions
correspond to the focal lesions seen earlier on MRI.
(A) Unilateral left hyperperfusion in a patient with herpes zoster encephalitis imaged 5
days after onset of symptoms. (B) Unilateral hypoperfusion in a patient with focal
encephalitis 3 months after onset. (C) Bilateral frontal hypoperfusion in a patient with
varicella-zoster encephalitis 4 days after onset. D) Normal SPECT scan in a patient with
encephalitis 3 days after onset
VZ encephalitis without rash
Typical picture is in immuno-compromised patient who
develops acute CNS disease or may have a history of
zoster weeks to months later or recurrent zoster. CNS
disease more often develops in the absence of acute
evidence of zoster.
 Encephalitis is ususally ‘small vessel’ type and the disease
is usually protracted.
 Acute VZ myelitis and aspetic meningitis may also occur
in the absence of a rash.
 ? Recent study suggests aetiology in up to 29% of cases of
Bell’s palsy
