Lives of the fellows

Peter Kynaston Thomas

b.28 June 1926 d.25 January 2008
CBE(1999) BSc Lond(1947) MB BS(1950) MRCS LRCP(1950) MRCP(1956) MD(1957) FRCP(1967) DSc(1971) FRCPath

As one of the foremost experimental neurologists, working from the 1950s, who took clinical neurology into the modern mechanistic era, Peter Kynaston Thomas combined an initial training in neurophysiology with expertise in neuropathology and, later, neurogenetics to develop important concepts on the aetiology, pathogenesis and phenotype of demyelinating and axonal peripheral neuropathies. He was a versatile, experienced and intuitive clinical neurologist who appeared to draw effortlessly on a vast range of knowledge in shaping his clinical opinions and writings. As a young man he styled himself ‘Peter Kynaston Thomas’, but in the late 1950s became known universally as ‘P K’ and that sobriquet stuck thereafter.

Born in Swansea, the eldest of three sons of Heber Leslie Thomas, timber importer and author, and his wife Beatrice Ida Carmen Thomas née Couch, Thomas was educated at the Parents’ National Education Union School, Swansea, and Emmanuel Grammar School. He matriculated at University College, London, as an open entrance scholar in 1944. Graduating BSc in 1947 and MB BS in 1950, he was a part-time demonstrator in anatomy at University College and part-time lecturer in physical anthropology at Birkbeck College, London, both from 1947 to 1950.

He did National Service with the Royal Army Medical Corps as a physiologist and secretary to the military personnel research committee from 1952 to 1954. Thomas held junior hospital appointments at University College Hospital and the Middlesex Hospital, London (from 1950 to 1957), trained in neurology at the National Hospital for Nervous Diseases, London (from 1957 to 1961), and was then briefly an assistant professor of neurology at McGill University, Montréal, before taking up appointments as neurologist to the Royal Free Hospital Group (1962 to 1991), the National Hospital (1962 to 1991) and the Royal National Orthopaedic Hospital, London (1966 to 1974).

With the establishment in 1962 of a professorial unit at Queen Square under the leadership of Roger Gilliatt [Munk’s Roll, Vol.IX, p.195], Thomas was appointed senior lecturer at the Institute of Neurology, University of London; he held a professorship in the University of London at the Royal Free Hospital School of Medicine from 1974 until his retirement in 1991. Thomas attended the teaching round chaired by Gilliatt each Wednesday afternoon at Queen Square. This gladiatorial event had many rules and rituals that were part of the folklore of the time. Seating was hierarchical and no one spoke unless invited so to do, and then almost never from a place further back than the second row behind which sat all trainees. On these occasions, Thomas was usually entrusted to elicit the physical signs and Gilliatt usually deferred to him for an initial opinion and formulation of the problem. As a beacon of common sense and clinical wisdom, his contributions were invariably illuminating. That he brought glad tidings of contemporary clinical science being championed elsewhere leavened the atmosphere and proved subtlety influential in the crucial but gradual resurgence of academic neurology at Queen Square beyond the 1960s. Whilst loyal to the National Hospital, the school of clinical neuroscience that Thomas nurtured at the Royal Free started the necessary process of devolving modern neurology away from Queen Square.

The shape of Thomas’ scientific career was set early. His life-long interest in the structure and function of the peripheral nervous system began through contact as an undergraduate with J Z (John Zachary) Young, who encouraged him to study the lateral line nerve of the trout. Thomas was quick to apply new techniques to the study of human peripheral nerve disease as the green shoots of experimental neurology emerged from the 1950s. His use of nerve biopsy, electrophysiology, electron microscopy, tissue culture, experimental models of common disorders such as the neuropathy that often complicates maturity onset diabetes, and eventually transgenic mouse models of human peripheral neuropathy, meant that his work over five decades remained innovative, creative and influential. Thomas showed first that, in health, nerve fibre diameter and internodal length determine the speed of electrical conduction, and, with Gilliatt, he described neurophysiological features that distinguish degeneration of peripheral nerve fibres from those disorders primarily causing loss of the surrounding myelin sheath. Later, work with his second wife Anita Harding [Munk’s Roll, Vol.X, p.190] led to a more comprehensive re-classification of genetically determined peripheral neuropathies. Many important discoveries relating to the mechanisms of inherited neuropathies and novel phenotypes followed during the rest of P K’s professional career. These always involved careful clinical and laboratory examination, sometimes performed in remote places: loss of vision and sensory neuropathy attributed to nutritional deficiency in Cuba (where evidently Fidel Castro took something of a liking to P K); hitherto unrecognised disorders of the Roma gypsies in Bulgaria; and, in the last clinical study with which he was directly involved, climbing to 15,000 feet in remote regions of the Peruvian Andes to perform nerve biopsies and conduction studies for a study of altitudinal neuropathy.

Thomas was a prodigiously energetic and diligent editor of neurological journals. From 1979 to 1981 he served with Marco Mumenthaler as co-chief editor of the Journal of Neurology (formerly Zeitschrift für Neurologie), and subsequently as editor of Brain (from 1982 to 1991) and the Journal of Anatomy (from 1990 to 2001). Colleagues remember him weighed down by his shoulder bag in which papers currently under consideration were carried anywhere and everywhere – in airport lounges, conference auditoria, restaurants, before and after out-patient clinics and at any time when no other essential activity was taking place he would be altering, polishing and invariably improving the style and narrative of these manuscripts. As editor of the Journal of Anatomy he revolutionised the appearance of the journal and modernised its content and distribution. Rigorous copy-editing of manuscripts was a skill honed in the 1970s when Thomas co-edited, with Peter Dyck and Edward Lambert, a monograph on Peripheral neuropathy (Saunders, W B, 1975). He also co-edited with Peter Dyck the second edition of the definitive work Diabetic neuropathy (Philadelphia, London, W B Saunders, 1987).

Outwardly shy, terse in his spontaneous conversation and capable of falling asleep in any company at any time, Thomas attracted and retained friends of many ages. He had an impish smile and sense of humour. He could entertain a small child sat on his knee with Welsh nursery rhymes, out-ski people half his age and offer penetrating intellectual conclusions in speech or writing whilst apparently dozing or listening intently to the minimalist, electronic and atonal modern compositions that seemed to resonate with the ancient rhythms of his Welsh roots.

Thomas married first Mary Truscott Cox. They had two sons, Adrian and Nicholas. Following her death in 1977, Thomas married Anita Elizabeth Harding, a trainee at the National Hospital and later professor of clinical neurology at the Institute of Neurology. Widowed a second time in 1995, Thomas married Sawanthana (‘Sam’) Ponsford née Hemachudha, a neurophysiologist. After suffering a large non-dominant ischaemic stroke with dense left hemiplegia and loss of spatial awareness, Thomas became house-bound for several years, but continued to spend time working, for the habit was engrained, and – apart from music, skiing and travelling in order to work and be in the company of his many professional friends around the world – he knew no other way of life. P K Thomas died of a chest infection at his home in West Hill Park, Highgate, and was survived by his wife Sam, two sons by his first marriage and his step-son.

Alastair Compston

[Compston A. ‘Thomas, Peter Kynaston (1926-2008).’ Oxford Dictionary of National Biography, Oxford University Press, Jan 2012; online edn, Jan 2013 – accessed 14 March 2015; Asbury AK, King RH, Reilly MM et al. ‘Professor P K Thomas: clinician, investigator, editor and leader – a retrospective appreciation.’ Brain. 2011 Feb;134(Pt 2):618-26]

(Volume XII, page web)

<< Back to List