The investigators propose to carry out a national retrospective study to collect epidemiological, biological, clinical and therapeutic data on microsporidiosis among heart transplant patients.

Microsporidia constitute a large family of intracellular eukaryotes infecting a wide range of hosts, ranging from insects to mammals and birds. Within this group, some species are responsible for intestinal syndromes manifested by abundant watery diarrhea, which can be particularly severe in immunocompromised individuals. In the 1980s, HIV-positive patients at the AIDS stage represented the primary population at risk. Nowadays, the most frequently affected patients among immunocompromised individuals are solid organ transplant recipients, for whom the management of this infection can be challenging. A neglected pathology until a few years ago, epidemiological data describing intestinal microsporidiosis in solid organ transplant recipients are scarce. The invesigators previously published the first data in kidney and liver transplant recipients. Here the investigators propose to carry out a national retrospective study to collect epidemiological, biological, clinical and therapeutic data on heart transplant patients.

Inclusion Criteria:

• heart transplant patients diagnosed with intestinal microsporidiosis
• diagnosis made before December 31, 2024 in France (metropolitan France and overseas territories)

Exclusion Criteria:

-patient opposition

Heart transplant patients with microsporidiosis