Dr Stephen B Walsh

I head the centre of Renal Physiology at UCL and while we do some animal work to unpick the underlying fundamental physiological processes, our focus is really on humans and specifically human renal tubular physiology. Our special interest is in disorders of sodium transport, blood pressure homeostasis, and the distal convoluted tubule (DCT).

The bedrock of the centre is the UCL Tubular Clinic, where we see patients with very rare renal tubular disorders, both inherited and acquired. We look after the largest cohorts of patients with Gitelman and Bartter syndrome in the UK, as well as large cohorts of patients with Gordon syndrome, distal renal tubular acidosis, the renal Fanconi syndrome, and other rarer electrolyte and acid–base disorders.

We conduct genetic studies for novel gene discovery (EAST syndrome, for example, was discovered here), carry out imaging studies of the hearts of Gitelman and Gordon syndrome patients and measure the urinary excretion of salts and exosomes in these patients when they are exposed to diuretics and other pharmacological agents.

This unusually dense collection of very rare human disease means that we have access to both patients and human biosamples, which have allowed Dr Keith Siew, a Sir Henry Wellcome Postdoctoral Fellow in the Centre training in micropuncture and imaging, to translate his findings from animal models to humans.

We have advanced imaging facilities and use modern optical clearing techniques to render human kidney tissue transparent (the methodology we use is called SHIELD). We then probe them with oligonucleotides, antibodies and/or stains and image them, using light sheet microscopy in 3D. We are developing this for rare disease basic research, comparative physiology, and new human diagnostic techniques, along with our consultant histopathologist, Dr Lauren Heptinstall, who is one of the researchers in the centre.