The centerpiece of Lévy’s reputation is a 1926 paper published in the Revue Neurologique, co-authored with Roussy, under a title that translates as Seven cases of a particular familial disease: gait disturbances, clubfeet and generalized tendon areflexia, with, incidentally, slight clumsiness of the hands. The seven patients, drawn from a single family, displayed a striking and reproducible combination of features. They walked with difficulty, a problem the authors captured in the term dystasia, and they had congenital or early-onset deformities of the feet. Most tellingly, their tendon reflexes were absent throughout, even though the clinical picture was far milder than that of the better-known hereditary ataxia of Friedreich, with which it was immediately compared.

The disorder they described became known as Roussy-Lévy syndrome, and its definition was a triumph of careful phenotyping. At a time when the tools of neurology were the hammer, the tuning fork, the ophthalmoscope and the clinical eye, Lévy and Roussy recognized that a syndrome could be defined by a constellation of signs rather than by any single finding. The combination of areflexia, pes cavus and other foot deformities, distal weakness and an essentially static or slowly progressive course distinguished their patients from those with Friedreich’s ataxia, who typically show pyramidal signs, scoliosis and cardiomyopathy, and from other hereditary neuropathies described in the same era. The 1926 paper stands as an early exercise in what would now be called genotype-phenotype correlation, conducted entirely at the bedside.

Lévy did not stop at description. In 1934, the year of her death, she and Roussy published a follow-up paper on hereditary areflexic dystasia framed as a contribution to the study of the genesis of familial diseases and their kinship with one another. That subtitle matters. The authors were explicitly wrestling with the question of how related clinical entities fit together, whether the syndrome they had described was a disease in its own right, a fruste or abortive form of Friedreich’s ataxia, or part of a broader family of hereditary degenerations. This was a conceptual debate that ran through French neurology of the period, and the 1933 paper by Darré, Mollaret and Landowski, which asked directly whether Roussy-Lévy disease was merely a mild form of Friedreich’s disease using labyrinthine and chronaxie examinations, shows how contested the boundaries remained.

The question was not settled for decades, and the eventual answer vindicated the distinctness of the syndrome in a way neither Lévy nor her contemporaries could have imagined. In 1956, Joseph Lapresle traced and re-examined four of the seven original patients, thirty years after the first publication, confirming the persistence of the phenotype and the remarkable stability of the clinical picture across the decades. Then, in 1973, Lapresle and Salisachs reported a finding that moved the debate from the clinic to the laboratory: a nerve biopsy specimen from one of the original cases of Roussy-Lévy disease showed onion bulb formations, the whorled proliferations of Schwann cell processes that are the pathological signature of a demyelinating and remyelinating hereditary neuropathy. The syndrome was, at its core, a disease of the peripheral nerves.

The molecular coda arrived at the end of the twentieth century. In 1998, Auer-Grumbach and colleagues demonstrated that the Roussy-Lévy syndrome is a phenotypic variant of Charcot-Marie-Tooth disease type 1A, associated with the characteristic duplication on chromosome 17p11.2 that underlies the commonest form of hereditary motor and sensory neuropathy. A year later, Planté-Bordeneuve and colleagues, in a paper pointedly titled The Roussy-Lévy family: from the original description to the gene, closed the loop by studying the descendants of the original kindred and confirming the genetic diagnosis. A clinical picture sketched in 1926 from seven patients and a family tree had been anchored, seventy-three years later, to a specific segment of the human genome.

That trajectory, from bedside description to chromosomal duplication, is precisely why historians of neuroscience find Lévy worth recovering. Her work illustrates how the great nosological debates of interwar neurology, over whether syndromes were separate diseases or variants of one another, were resolved not by better rhetoric but by accumulated follow-up data and, eventually, by molecular genetics. The Roussy-Lévy syndrome is now understood as part of the demyelinating Charcot-Marie-Tooth spectrum, yet its recognition as a distinct phenotype in 1926 helped clinicians for decades to counsel families, predict prognosis and distinguish patients whose disease would remain relatively static from those facing the progressive disability of Friedreich’s ataxia.

Lévy’s scientific range extended beyond hereditary neuropathy. In 1925 she published a monograph on the late manifestations of epidemic encephalitis, the prolonged and delayed forms of the disease that swept Europe in the wake of the First World War and left many patients with parkinsonian and other sequelae years after the acute infection. The work places her among the clinicians who grappled with encephalitis lethargica, one of the great unsolved puzzles of the era, and shows a career that engaged with both the degenerative and the infectious frontiers of neurology. Contemporaries remembered her within the vibrant Parisian school that included figures such as Jean Lhermitte, and the historical literature, notably Peter Koehler’s 2018 study of Lévy and the Roussy-Lévy syndrome in the Journal of the History of the Neurosciences, has begun to piece together the details of her short but productive career.

Her early death in 1934, at the age of forty-eight, cut short a career that had already produced two landmark papers on hereditary areflexic dystasia and a substantial monograph on post-encephalitic disease. It also helps explain why her name faded. Eponyms tend to attach to those who survive to promote, extend and defend their syndromes, and Lévy had no such opportunity. The new biographical account, written by Carlos Alvarado-De la Hoz, Andres Felipe Cardenas-Cruz and Alba Lucia Marentes-Cubillos, neurologists at the Hospital Universitario San Ignacio and the Pontificia Universidad Javeriana in Bogotá, forms part of a deliberate effort by the Journal of Neurology to document the pioneers whose contributions underpin modern practice, and it appeared in volume 273 of the journal as article number 601.

For a modern readership, the story carries a broader lesson about how medicine accumulates knowledge. The seven patients described in 1926 were examined with none of the instruments that would eventually explain their condition, yet the precision of the original observation was good enough that a biopsy in 1973 and a gene study in 1999 could be anchored to those very cases. Clinical description, often dismissed as the antiquarian wing of neuroscience, proved to be durable data. Gabrielle Lévy’s legacy is a reminder that the careful documentation of a single family, done well, can outlast the career and even the life of the observer, and that some of the most consequential figures in the history of the neurosciences are those whose names survive only in the hyphen of a syndrome they never lived to see explained.

Subject of Research: Historical biography of neurologist Gabrielle Lévy and the Roussy-Lévy syndrome

Article Title: Gabrielle Lévy (1886–1934)

Article References: Alvarado-De la Hoz, C., Cardenas-Cruz, A. F., & Marentes-Cubillos, A. L. (2026). Gabrielle Lévy (1886–1934). Journal of Neurology, 273(10), Article 601. https://doi.org/10.1007/s00415-026-14135-y

Image Credits: AI Generated

DOI: 10.1007/s00415-026-14135-y

Keywords: Gabrielle Lévy, Roussy-Lévy syndrome, hereditary areflexic dystasia, Charcot-Marie-Tooth disease, Friedreich's ataxia, neurology history, hereditary neuropathy, peripheral nerve, genetics, Pioneers in Neurology, Journal of Neurology, medical eponyms

Friedreich’s ataxia is a recessive genetic disorder that strikes in childhood or adolescence, progressively robbing patients of coordination, strength, and sensation. In roughly 96 percent of cases, it is caused by biallelic expansions of a GAA repeat sequence within the FXN gene, which silences production of frataxin, a protein essential to mitochondrial function in cells. The deficit cascades across multiple organ systems: the central and peripheral nervous systems degenerate, the heart muscle thickens into hypertrophic cardiomyopathy, the pancreas falters toward diabetes, and scoliosis, spasticity, and optic neuropathy often follow. Most therapeutic strategies now in development aim either to soften the downstream consequences of frataxin loss or to restore frataxin expression directly, through gene therapy delivered by adeno-associated viral vectors, protein replacement, or epigenetic reactivation of the damaged gene.

The idea that transplanted blood-forming cells might help the brain rests on an intriguing biological premise. Cells of the monocyte lineage can, under certain conditions, migrate into the central nervous system and potentially exchange material with resident brain cells, raising the possibility that donor-derived cells could act as delivery vehicles for frataxin to deficient tissue. The concept carries real appeal but also unresolved risks, and the mechanisms that would make it work have never been fully defined. The patient described in the new report, who underwent a complete stem cell replacement for reasons entirely unrelated to her ataxia, offered a natural test of whether such replacement could alter the disease course.

Her medical odyssey began at age ten, when chest pain and a racing heartbeat landed her in the intensive care unit with thyrotoxicosis. During that hospitalization, doctors noted persistent cytopenias, and a bone marrow aspirate revealed acute myeloid leukemia carrying the t(6;9) translocation, a high-risk subtype with a strong tendency to relapse. At the same time, subtle neurological signs emerged: a slightly wide-based gait with externally rotated legs, ataxia, faint tremors confined to her fingers, diminished vibratory sensation, and absent deep tendon reflexes. Genetic testing confirmed biallelic GAA expansions in FXN of 699 and 1066 repeats, establishing the diagnosis of Friedreich’s ataxia, and an echocardiogram revealed moderate left ventricular hypertrophy, the disease’s characteristic cardiac signature.

Treating the leukemia in a child with a fragile heart demanded a delicate balancing act. Induction chemotherapy with a dose-adjusted regimen of cytarabine, daunorubicin, and etoposide failed to achieve remission, forcing a switch to a salvage combination of topotecan, vinorelbine, thiotepa, and clofarabine, which succeeded in driving the leukemia to minimal residual disease negativity after two cycles. She then received an allogeneic hematopoietic stem cell transplant from an 11-of-12 HLA-matched unrelated male donor, using CD34-positive selected peripheral blood stem cells. Her conditioning regimen combined rabbit anti-thymocyte globulin, clofarabine, melphalan, and thiotepa. Remarkably, the procedure proceeded without major unexpected complications, no graft-versus-host disease developed, and she has remained in leukemia remission for the entire decade since.

The neurological story, however, unfolded exactly as it would have without the transplant. Over ten years, her speech became mildly affected, her gait and arm function worsened, and her reflexes and peripheral neuropathic components showed no reversal. Quantitative measures told the same story: her modified Friedreich Ataxia Rating Scale score climbed by 20 points, and her nine-hole peg test times doubled, tracking the trajectory of six comparator patients at the same institution who had similar GAA repeat lengths and ages of onset but received no transplant. She now uses a wheelchair and cannot ambulate independently, and she developed diabetes and sleep apnea along the way. In short, a fully successful bone marrow replacement did nothing to touch the degeneration in her nervous system.

The authors of the report point to several converging reasons why. The blood-brain barrier excludes most donor-derived cells from entering the brain’s parenchyma, and conventional stem cell transplantation does not achieve the deep microglial and monocyte depletion that some researchers believe would be necessary for donor cells to meaningfully repopulate the central nervous system. Frataxin itself is an intracellular mitochondrial protein, which means donor cells cannot perform the kind of cross-correction seen in some other metabolic storage diseases, where secreted enzymes rescue neighboring cells. Friedreich’s ataxia also carries significant developmental components, so replacing frataxin after the developmental window may simply come too late to rescue already-compromised neural circuits. Finally, the chemotherapy required to conquer her leukemia may itself have aggravated her neuropathy, and her secondary diabetes could have blunted any residual benefit.

Yet the case contains one genuinely striking observation. While her neurological scores marched steadily downward, her cardiac hypertrophy stabilized. Ten years after the transplant, her echocardiogram was read as normal, and comparisons of her ejection fraction and intraventricular septal diameter against the six matched comparator patients suggested her heart measures had held steady where others continued to change. The authors urge caution in interpreting this, noting that wall thickness in Friedreich’s ataxia is only modestly predictive of long-term outcome, that reductions in wall thickness can occur without lasting benefit, and that some comparator subjects showed similar stabilization. Ejection fraction changes are typically late phenomena in the disease, so a decade of stability is notable but not definitive proof of cardiac protection.

The clearest confirmation of the transplant’s biological success came from her blood. Genetic testing performed ten years after the procedure showed GAA repeat lengths of 10 and 16, entirely normal values reflecting the donor’s healthy genome, and her blood frataxin levels had returned to the control range, measured at 4.79 nanograms per milliliter for the mature form and 9.25 for the extended form. Her hematopoietic system had been completely rebuilt from genetically unaffected donor cells, demonstrating that full donor chimerism and normalized frataxin production in blood are achievable in a Friedreich’s ataxia patient, even if the nervous system remained beyond reach.

Because Friedreich’s ataxia is not known to elevate cancer risk, the co-occurrence of leukemia in this patient was almost certainly coincidental, but it dramatically complicated her treatment, given the cardiac sensitivity and neurotoxicity risks posed by many chemotherapy agents. The successful outcome nonetheless establishes that Friedreich’s ataxia patients can survive allogeneic stem cell transplantation, just as they have survived heart and liver transplantation in prior reports, opening a door for treating hematologic malignancies in this population. And the hint of cardiac stabilization, combined with the procedure’s relative safety, keeps alive the possibility that stem cell approaches could one day benefit the disease, if deployed in paradigms specifically engineered to deliver frataxin to the central nervous system. The authors are careful to stress that the present observations cannot be taken as evidence of neurological benefit, but the case stands as a rare, decade-long natural experiment that maps both the promise and the hard biological limits of replacing a patient’s blood to heal a brain.

Subject of Research: Allogeneic stem cell transplantation in a patient with Friedreich's ataxia and acute myeloid leukemia

Article Title: Stem Cell Transplantation in Friedreich Ataxia: Cure for Leukemia but No Effect on Neurological Progression

Article References: Gitman, A., Bhandari, N., Castellaro, M., Schadt, K., Cancio, M., & Lynch, D. R. (2026). Stem Cell Transplantation in Friedreich Ataxia: Cure for Leukemia but No Effect on Neurological Progression. Annals of Clinical and Translational Neurology, 13(8), 1733-1735. https://doi.org/10.1002/acn3.70455

Image Credits: AI Generated

DOI: 10.1002/acn3.70455

Keywords: Friedreich's ataxia, stem cell transplantation, frataxin, acute myeloid leukemia, FXN gene, neurodegeneration, cardiomyopathy, blood-brain barrier, gene therapy, GAA repeat expansion, hematopoietic stem cells, case report