Autoimmune Limbic Encephalitis in a Patient with Acute Encephalopathy and Hyponatremia

Table 1

Parameter	Result	Reference range
Blood/serum studies
Hemoglobin	12.9 g/dL	11.7–16.5 g/dL
Hematocrit	38.7%	35.7–45.8%
WBC count	10.5 k/mm^3	4–11 k/mm3
Platelet count	382 k/mm^3	150–460 k/mm^3
Sodium	127 mmol/L	133–145 mmol/L
Potassium	3.8 mmol/L	3.8–5.2 mmol/L
Chloride	88 mmol/L	98–107 mmol/L
Bicarbonate	27 mmol/L	22–29 mmol/L
Anion gap	12	4–17
BUN	5 mg/dL	6–20 mg/dL
Creatinine	0.6 mg/dL	0.5–1.0 mg/dL
Serum osmolality	257 mOsm/kg	280–290 mOsm/kg
TSH	1.64 IU/L	0.4–4.0 IU/L
Free T4	1.08 ng/dL	0.7–1.8 ng/dL
AST	17 U/L	0–32 U/L
ALT	16 U/L	0–33 U/L
Alkaline phosphatase	86 U/L	35–104 U/L
Total bilirubin	0.5 mg/dL	0–1.2 mg/dL
Vitamin B12	278 pg/mL	232–1245 pg/mL
Calcium	9.4 mg/dL	8.6–10.5 mg/dL
Phosphorous	3.8 mg/dL	2.5–4.5 mg/dL
Magnesium	1.8 mg/dL	1.6–2.3 mg/dL
Glucose	117 mg/dL	70–99 mg/dL
Uric acid	2.8 mg/dL	1.6–7.6 mg/dL
Cortisol (7am)	26 ug/dL	6–18.4 ug/dL
Urinary studies
Urine osmolality	486 mOsm/kg	50–1400 mOsm/kg
Urine sodium	87 mmol/L	20 mmol/L
Urine barbiturate, cannabinoid, cocaine, benzodiazepine, amphetamine, opiate, oxycodone	Not detected	Not detected
Cerebrospinal fluid studies
Opening pressure	21 cmH20	<20 cmH20
Color	Clear	Clear
WBC	3	0–5
RBC	1	0
Total protein	18 mg/dL	15–60 mg/dL
Glucose	69 mg/dL	50–80 mg/dL
Oligoclonal bands	3	<5
IgG index	0.86	0.30–0.77
Meningoencephalitis PCR panel	Negative	Negative
CSF gram stain and culture	Negative	Negative
CSF AFB smear	Negative	Negative
CSF AFB culture	Negative	Negative
CSF fungal culture	Negative	Negative