Acute kidney injury, seizures, and hypertonic hyponatremia secondary to mannitol intoxication in a dog

OBJECTIVE

To describe a case of mannitol overdose associated with acute kidney injury (AKI), hypertonic hyponatremia, and neurologic abnormalities in a dog.

CASE SUMMARY

A 10-year-old intact male Shiba Inu dog was referred to the emergency service of a veterinary teaching hospital for inappetence and acute onset of seizures. The dog had received 2 IV boluses of 3 g/kg of mannitol in less than 24 hours for a glaucoma crisis. Twelve hours after the second injection, the dog became inappetant and developed 2 generalized seizures. Seizure activity was treated with diazepam (0.5 mg/kg IV). Serum biochemistry profile showed severe hyponatremia and hypochloremia, mild hypokalemia, marked increased creatinine (381 µmol/L [44-133 µmol/L]) and moderately increased BUN (13.8 mmol/L [1.6-10.9 mmol/L]). Urinalysis revealed a urine specific gravity of 1.018, glucosuria, proteinuria, pigmenturia and the presence of vacuolized tubular epithelial cells. A presumptive diagnosis of mannitol intoxication was made based on the high dose of mannitol, severe hyponatremia, neurological abnormalities suggestive of intracranial disease, AKI, and urine cytology. Initial calculated plasma osmolality was 263.4 mOsm/kg and measured plasma osmolality was 332 mOsm/kg with an osmolal gap of 68.6 mOsm/kg, confirming the presence of an unmeasured solute attributed to mannitol. Treatment consisted of fluid therapy and supportive care. On day 3, osmolal gap had resolved and serum creatinine concentration returned to normal within 12 days.

NEW OR UNIQUE INFORMATION PROVIDED

Mannitol intoxication has been reported in human medicine. This case report is, to our knowledge, the first to describe AKI, hypertonic hyponatremia, and neurological abnormalities secondary to mannitol overdose in a dog.

Osmotic nephrosis with mannitol: review article

Mannitol is commonly used to lower intracranial and intraocular pressures. Large doses/massive infusions of mannitol have been found to be associated with acute renal failure (MI-ARF), that is, osmotic nephrosis. While many researchers have reported individual experiences with this pathology, we felt that there is need of an updated comprehensive review of all reported cases with elaboration of etiology, pathogenesis, diagnosis and management plan for MI-ARF. The purpose of the present communication is to share our own experience with MI-ARF, to review the effect of mannitol on kidney function and to highlight the dynamics of MI-ARF with considerations for the cautious use of mannitol in patients with risk factors for kidney diseases.

Renal transplants from non-heart beating paracetamol overdose donors

INTRODUCTION

Non-heart beating donors (NHBD) are widely encouraged to avert the critical shortage in the kidney donor pool. Ischaemic injury at the time of cardiac arrest in the NHBD is more pronounced and therefore the kidneys resulting are considered marginal. This review describes our experience with four kidneys from two controlled NHBDs who were exposed to paracetamol intoxication and subsequently were treated with mannitol prior to organ donation.

MATERIALS AND METHOD

Two patients with fulminant liver failure following paracetamol overdose were referred as 'withdrawal of treatment' NHBD. As the two patients had developed hepatic encephalopathy they were treated with mannitol to reduce intra-cerebral oedema. The two donors were oligoanuric for at least 24 h prior to cardiac arrest. Following cardiac arrest, in situ perfusion was carried out and the kidneys were removed. One pair of kidneys were machine perfused while the second pair of kidneys were cold stored prior to transplantation.

RESULTS

Pre-transplant assessment of NHBD kidneys resulted in three of four kidneys being transplanted. The NHBD kidneys exhibited a period of delayed graft function (DGF). The early transplant biopsies showed evidence of diffuse cytoplasmic vacuolation. These histological features disappeared with time and the renal function improved until the time of discharge.

DISCUSSION

Non-heart beating donor kidneys are considered marginal and the effect of mannitol and paracetamol drug intoxication will induce reversible sub-lethal injury. A period of dialysis is inevitable in clearing the reactive intermediates of mannitol and paracetamol. The kidneys behaved as traditional controlled NHBD at time of discharge.