A diarrhoeal blast from the past

Diarrhoea is a common presentation in travellers. This case highlights the importance of providing the microbiology laboratory with necessary clinical information so that special media can be inoculated in order to establish a prompt diagnosis.

A 29 year-old male was admitted in Glasgow, UK with a 24 hour history of profuse watery diarrhoea. He was travelling from Mumbai, India. He reported no relevant sick or healthcare contacts. On admission he was dehydrated, tachycardic, and hypotensive. Blood testing revealed normal electrolytes but lactic acidosis, a severe AKI, neutrophilia, and raised CRP. Treatment was initiated with IV fluids, empirical IV ceftriaxone and azithromycin. Urine, faeces and blood cultures were collected and rectal screening for CPE was performed. More than 6L of diarrhoea was passed in the first 12 hours.

Over the subsequent 48 hours diarrhoea continued while urine output and biochemistry normalised with IV fluids. Yellow colonies were grown from faecal cultures on TCSB agar. Gram stain revealed short, ‘comma-shaped’ gram negative aerobic rods. These were identified asVibrio choleraeusing MALDI-TOF and later confirmed to be serotype 01 El Tor. Rectal swabs returned positive for NDM-1 producing Escherichia coli. By the third day his diarrhoea resolved, antibiotics and IV fluids were discontinued and he was discharged.

This case highlights the challenge of managing V. cholerae infection in a traveller. Cholera should be considered in the differential diagnosis of diarrhoea in any traveller and specific laboratory testing is required to make a positive diagnosis.