Claus Bruns

In memory of Prof. Dr. Claus Brun (1914 – 2014)

At the death of Claus Brun, a few months after his 100 years Birthday, Danish, European and International Nephrology have lost one of their great founding personalities.

Claus Brun was a nephrological pioneer, who in the late 40s introduced the technique of performing a percutaneous kidney biopsy. He created the basis for our understanding of renal histopathology and its correlation with functional and clinical data. He eagerly participated in the international exchange of ideas during these early days and became the President of the International Society of Nephrology (ISN) from 1963 to 1966.

Claus Brun was born in 1914 in Copenhagen. He graduated from University of Copenhagen in 1940. Claus Brun worked for almost his entire professional life at the Municipal Hospital in Copenhagen until his retirement in 1984.

Claus Brun became specialist in Clinical Biochemistry in 1948 and in Nephrology in 1969.
Together with Poul Iversen, Claus Brun was the first to publish the method of doing a percutaneous kidney biopsy in their classic  paper, "Aspiration Biopsy of the Kidney" in Am J Med 11:324-330, 1951. The authors obtained adequate biopsy tissue in 42 out of 66 patients with a minimum of bleeding complications. They also described the ability to make diagnoses of amyloidosis, diabetic nephropathy, hypercalcemia, and glomerulonephritis based on the pathology.The percutaneous kidney biopsy has ever since created the possibility of obtaining the correct diagnosis and as such provide the optimal treatment for a very large number of patients worldwide with kidney diseases.

In 1956, Jean Hamburger, at the L'hôpital Necker invited Claus Brun to come to Paris and demonstrate the kidney biopsy technique and the histological results, leading to establishment of an international network of scientists interested in kidney function and disease. In 1960 they organized the First International Congress of Nephrology with 400 participants. Jean Hamburger became the first President and Claus Brun the second President of ISN. He became President of the Danish Society of Nephrology in 1969 and was awarded the prestigious Novo Nordic Award in 1964 and later he received the Knight's Cross of the Order of the Dannebrog.

Claus Brun’s way to nephrology was based upon a lifelong scientific and clinical interest in patients with acute and chronic kidney diseases. His doctoral thesis from 1954 was on:” Acute anuria, A Study based on renal function tests and aspiration biopsy of the kidney”  and was based upon his clinical observations at the Municipal Hospital in Copenhagen, his work at Department of Clinical Biochemistry, and based upon experiences from his sebatical in USA at Department of Physiology, New York University og Mt. Desert Island Biological Laboratory, Maine, where he from 1952 to 1953 had the great fortune to work together with Homer Smith.

He was interested in clinical nephrology and in the physiological aspects of acute and chronic kidney failure and was the first in Denmark to introduce an artifical kidney. Claus Brun published a large number of scientific papers, many in the best scientific medical journals.

Claus Brun became Chief Physician in 1956  at the Department of Clinical Biochemistry at the Municipal Hospital in Copenhagen, and created there his lab of kidney pathology. Claus Brun was known all over the world for his high quality work, his biopsies were always of the best quality and the careful description always at the highest level. His histological work has for years been the golden standard and his histological atlas on glomerulonephritis together with Steen Olsen used all over the World.

Claus Brun had a number of interests beside his scientific fascination of kidney biopsies.
Thus, in1968 he and his wife, Xenia, were invited to visit Butan. They became involved in treatment of patients and made an assessment of the overall health situation. Claus Brun went back in 1979, and suggested that the Bhutanese requested the Danish authorities for a hospital and back-up training.
Claus Brun was an eager iceskater and was always the first on the ice of the small lake where he lived.

The World has, at the death of Claus Brun, lost a briliant and engaged nephrologist, from whom we have learned a lot. Our thoughts and sympathy go to Xenia, Claus Brun’s wife, who through all the years has been a deeply involved partner in the life of Claus Brun, and to his daughter and son-in-law.

Copenhagen, October 4, 2014

Bo Feldt-Rasmussen, Lisbet Brandi & Klaus Olgaard