1. Lithium Toxicity

2. CC: 66 yom + AMS + ~3 days HPI:
66 yom with PMH significant for HTN, CKD-IV, CHF, diabetes, hypothyroidism, HDL, gout, PTSD, and schizoaffective disorder presents with 3 days of altered mental status. Patient states that Vietnamese soldiers were chasing him to the foot of his bed and that he couldn’t walk. He complained of “shaking.” He also was experiencing memory lapses and was unable to recall his transfer from an outside hospital. 

3. ROS: Blurry Vision Dizziness Decreased energy Irritability
Nausea/Vomiting
Abdominal pain
Shaking
Polydipsia
Polyurea
Bowel incontinence
Generalized pain

4. PMH: HTN, CKD-IV, CHF, diabetes, hypothyroidism, HDL, Gout, PTSD, schizoaffective disorder, various vitamin deficiencies
Medications: Allopurinol, Amlodipine, ASA, Atorvastatin, Tylenol #3, Gabapentin, Insulin, Levothyroxine, Lisinopril, Lithium, Metoprolol tartrate, Mirtazapine, Omeprazole, Sertraline
Allergies: Maxzide, Quetiapine, Risperidone
Social history: Vietnam vet, 100% SC, lives at home with his wife. Remote smoking, heavy alcohol, and IV Drug use. Brother died in the past week, patient smoked marijuana at the funeral

5. Vitals: BP: 221/92 P: 61 T: 98.8 R: 18 Po2: 94% BMI: 39.5
Physical Exam
Gen: Difficult to arouse, oriented to self, year is 2020, location is outside hospital, groaning
HEENT: NC/AT, PERRL, sclera non-icteric, MMM
CV: RRR, no M/R/G
Resp: No respiratory distress, CTAB
GI: +BS, obese, mild tenderness to palpation, no rigidity or guarding
Extremities: No edema, clubbing, or cyanosis
Skin: Warm, dry, no rashes
Neuro: Some stuttering, repetitive speech, no involuntary movements or tremors, no facial drooping, moves extremities against gravity

6. PAUSE
Differential diagnosis
Audience requests labs/imaging 

7. Labs: Na: 145, Cr: 2.37
UDS: +MJ/opiates
Ammonia: 18
Lithium: 0.82
CT OSH: no acute intercranial abnormality
MRI Brain: unable to tolerate
ECG: no changes

8. PAUSE
Differential diagnosis part 3
Audience votes on diagnosis

9. Lithium Toxicity Presentation:
Neurotoxicity: tremor, hyperreflexia, AMS (confusion to delirium)
Nausea/vomiting/diarrhea 
Hypernatremia
Nephrogenic diabetes insipidus
Endocrinopathies: Hypothyroidism/hyperparathyroidism

10. Diagnosis Lithium has a narrow therapeutic index
Associated with polypharmacy and medical comorbidities
Lithium levels, CBC, electrolytes, BUN and Cr
Mild symptoms: nausea, vomiting, lethargy, tremor, and fatigue (Serum lithium concentration between mEq/L).
Moderate intoxication: confusion, agitation, delirium, tachycardia, and hypertonia (serum lithium concentration between  mEq/L).
Severe intoxication: Coma, seizures, hyperthermia, and hypotension (serum lithium concentration (less than 3.5 mEq/L).

11. Treatment
Discontinuation of drug
IVF
Hemodialysis

12. References Uptodate: Lithium poisoning
Sun, M., Herrmann, N. & Shulman, K.I. Clin Drug Investig (2018) 38: