History suggestive of sepsis – cold, unwell, recurrent UTI’s, recent antibiotics

Bladder/ Prostate resection – does this patient have a ureterostomy?

pH 7.10, HCO3 11 – severe metabolic acidosis

Anion gap =13 – normal ie. normal anion gap (hyperchloraemic) metabolic acidosis [NAGMA]

Delta ratio <0.4, therefore pure NAGMA

Delta ratio = (AG -12)/(24-HCO3)

Glucose 19.8 – high – ketones not given but DKA unlikely

Lactate normal

WCC 13.9, N 12.2 – ?sepsis

Interpretation – 69 year old man with severe non anion gap metabolic acidosis, likely secondary to ureterostomy (exclude other causes…), possible sepsis (urosepsis, other), hyperglycaemia (likely non ketotic).

This patient requires early antibiotics, HCO3 infusion and admission until acidosis is corrected.

Uresterostomy – ureter is connected to sigmoid colon. Risks of this include:

1. Infection – faeces can enter ureter and spread proximally – may req prophylactic antibiotics

2. Urine in colon causes diarrhoea and acid base disorders

Na is swapped for K which can cause hyperK.

Cl is swapped with HCO3 which causes NAGMA – patient are often on HCO3 tablets

3. Urea can be elevated because it is absorbed in the gut.

This patient indeed had a ureterostomy as the cause of his presentation. He was treated with HCO3 infusion and discharged on oral HCO3 tablets.