Myoclonic Jerks, Exposure to Many Cats, and Neurotoxoplasmosis in an Immunocompetent Male

Antonio Jose Reyes; Kanterpersad Ramcharan; Stanley Lawrence Giddings; Samuel Aboh; Fidel Rampersad

doi:10.5334/tohm.408

Figures & Tables

Video 1

Demonstration of Myoclonic Jerks in our Patient. This video shows multifocal, myoclonic jerks of the patient’s head, right upper limb, fingers, and legs. These involuntary intermittent jerky movements took place during the day or night but only during sleep without causing incontinence or arousal. We found an observable pattern of three to five sequences of muscle contractions per minute, each lasting 2–3 minutes followed by a period of non- observable phenomena of 20–30 minutes’ duration. These movements occurred four to six times daily for 7 days. Myoclonus was not observed after spontaneous arousal or while the patient was awake. The patient was always unaware of those events that subsided spontaneously without benzodiazepines.

Table 1

Medical Investigations

Tests Performed on Admission	Result	Reference Range
Blood test
WBCs	13.8 × 10⁹/L	4.5–11.0 × 10⁹/L
Eosinophils	14.1%	0.0–0.6%
Hemoglobin	15.2 g/dL	14.0–17.5 g/dL
Mean corpuscular volume	83.2 fL/red cell	80–96 fL/red cell
Platelet count	350 × 10³/µL	156–373 × 10³/µL
Serum potassium	4.1 mmol/L	3.5–5.1 mmol/L
Serum sodium	138 mmol/L	135–145 mmol/L
Serum creatinine	0.8 mg/dL	0.5–1.2 mg/dL
BUN	11 mg/dL	3–20 mg/dL
Uric acid	4.5 mg/dL	2.5–8 mg/dL
Alanine aminotransferase	60 IU/L	20–60 IU/L
Aspartase aminotransferase	40 IU/L	5–40 IU/L
Gamma glutamyl transpeptidase	60 U/L	8–61 IU/L
Lactate dehydrogenase	330 IU/L	105–333 IU/L
Alkaline phosphatase	129 U/L	40–129 IU/L
Albumin	4.9 g/dL	3.5–5.5 g/dL
Albumin-corrected calcium	9.6 mg/dL	9.6–11.2 mg/dL
CRP	31.1 mg/dL	0.0–1.0 mg/dL
Fasting blood sugar	80 mg/dL	60–120 mg/dL
VDRL test	Non-reactive	Non-reactive or reactive
FTA-ABS	Negative	Positive or negative
Elisa for HIV	Non-reactive	Non-reactive or reactive
Antistreptolysin O titer	90 IU/mL	0–200 IU/mL
Toxoplasma gondii IgG antibodies	198 IU/mL	Positive: greater than 1.09 IU/mL
Toxoplasma gondii IgM antibodies	Positive	Positive or negative
Toxoplasma gondii specific IgG avidity	High avidity (AI > 50%)	Low avidity (AI ≤ 50%)High avidity (AI > 50%)
Herpes virus 1 IgG antibodies	Less than 0.9	Index negative: Less than 0.9
Herpes virus 1 IgM antibodies	Less than 0.9	Index negative: less than 0.9
Herpes virus 2 IgG antibodies	Less than 0.9	Index negative: Less than 0.9
Herpes virus 2 IgM antibodies	Less than 0.9	Index negative: less than 0.9
CMV IgG antibodies	0.800 UA/mL	Negative: less than 1.5 UA/mL
CMV IgM antibodies	0.778 UA/mL	Negative: less than 1.1 UA/mL
EBV IgG antibodies	3.3	Positive: Greater than 22
EBV IgM antibodies	0.1	Negative: less than 0.8
Hepatitis BsAG	Negative	Positive or negative
Hepatitis C IgG antibodies	Negative	Positive or negative
Hepatitis C IgM antibodies	Negative	Positive or negative
Echinococcus granulosus IgG antibody	Negative	Positive or negative
Anti-double stranded DNA	Negative	Positive or negative
Antinuclear antibody	Negative	Positive or negative
Perinuclear antineutrophil cytoplasmic antibodies	5.42 U/mL	Negative: less than 10.0 U/mL
Cytoplasmic antineutrophil cytoplasmic antibodies	3.73 U/mL	Negative: Less than 10.0 U/mL
PCR for viral infections or toxoplasmosis	Tests not obtained	Negative or positive
Other investigations
Mantoux test	Negative	Positive or negative
Electrocardiogram	Sinus tachycardia	Normal or abnormal
Chest X-ray	Normal	Normal or abnormal
Echocardiogram	Normal ejection fraction 75%	Normal or abnormal
CT scan of the brain with contrast	Normal	Normal or abnormal
MRI/MRA scans of the brain	Normal	Normal or abnormal
CSF analysis	CSF opening pressure was 14 cm of H₂O. CSF contained 47 cells/mm³, 0.8 g/L of proteins, and the glucose concentration was 60 mg/dL. CSF culture showed no bacterial growth and cytology was negative for neoplastic cells. VDRL was non-reactive and India ink test for Cryptococcus neoformans was negative
Toxoplasma gondii IgG antibodies in CSF	20 IU/mL	Positive: greater than 1.09 IU/mL
Toxoplasma gondii IgM antibodies in CSF	Positive	Positive or negative
Tests performed in the follow-up blood test
Toxoplasma gondii IgG antibodies	20 IU/mL	Positive: greater than 1.09 IU/mL
Toxoplasma gondii IgM antibodies	Positive	Positive or negative
PCR for viral infections or toxoplasmosis	Tests not obtained	Negative or positive
Other investigations
Scalp EEG	Normal	Normal or abnormal
EMG and nerve conduction studies	Normal	Normal or abnormal
PCR for viral infections or toxoplasmosis in CSF	Tests not obtained	Negative or positive
Video-EEG, polysomnography and jerk locked backed averaging studies	Tests not obtained	Normal or abnormal

[i] Abbreviations: BUN, Blood Urea Nitrogen; BsAG, B surface antigen; CMV, Cytomegalovirus; CRP, C-reactive Protein; CSF, Cerebrospinal Fluid; CT, Computed Tomography; DNA, Deoxyribonucleic Acid; EBV, Epstein–Barr Virus; EEG, Electroencephalogram; ELISA, Enzyme-linked Immunosorbent Assay; EMG, Electromyography; FTA-ABS, Fluorescent Treponema Pallidum Antibody Absorption; HIV, Human Immunodeficiency Virus; Ig, Immunoglobulin; MRI/MRA, Magnetic Resonance Imaging/Magnetic Resonance Angiography; PCR, Polymerase Chain Reaction; VDRL, Venereal Disease Research Laboratory; WBC, White Blood Cell.

Table 2

Medical Treatment

	Dosage	Period of Treatment
Intravenous therapy initiated on admission day
Trimethoprim–sulfamethoxazole	160 mg/800 mg 3 times daily	2 weeks
Normal saline isotonic solution	1 L daily	1 week
Pantoprazole	40 mg twice daily	3 days
Oral drugs initiated on admission day
Carbamazepine	200 mg 2 times daily	6 days
Paracetamol	1 g three times daily	7 days
Other oral drugs
Trimethoprim–sulfamethoxazole	80 mg/400 mg per tablet 2 tablets 2 times daily	4 weeks initiated on day 15
Pantoprazole	40 mg once daily	14 days initiated on day 4

Table 3

Differential Diagnosis of the Causes of Myoclonus

Causes	Disease states
Endocrine	Hyperosmolar hyperglycemic state
Ischemic states	Brain hypoxia, strokes
Vasculitis	CNS vasculitis
Autoimmune	Systemic lupus erythematosus
Drugs	Tramadol, morphine, hydromorphine, pethidine, quinolones, benzodiazepine, gabapentin, sertraline, lamotrigine, and any drug or chemical poisoning
Infection–sepsis	Neurosyphilis, HIV encephalopathy, CNS toxoplasmosis in HIV-AIDS, Lyme disease
Neurodegenerative	Parkinson’s disease, multiple sclerosis, Alzheimer’s disease
Trauma	Head or spinal cord injury
Neoplasia	Brain tumors
Genetic	Mitochondrial encephalomyopathy, lipid storage disease
Organ failure	Kidney or liver failure
Other causes	Negative myoclonus, tremor, opsoclonus myoclonus syndrome, Creutzfeldt–Jacob disease, Tourette syndrome

[i] Abbreviations: AIDS, Acquired Immune Deficiency Syndrome; CNS, Central Nervous System; HIV, Human Immunodeficiency Virus.