Study objective: To evaluate phenotypic variability of lysinuric protein intolerance in a cohort of nine Italian patients.
Design: Retrospective analysis of patient records.
Subjects: Nine Italian patients (seven independent families), all originating from southern Italy, observed during the last 14 years.
Results: Some of the patients had unique clinical features, including bone marrow abnormalities featuring erythroblastophagocytosis (five patients) and clinical course and the outcome of the disease, have also been observed: respiratory involvement was present in five cases, with a lethal picture of "alveolar proteinosis" in one. Severe kidney involvement, with both glomerular and tubular damage and rapidly progressing to chronic renal failure, has been observed in one case.
Conclusion: Lysinuric protein intolerance may cause severe multisystem involvement, which requires early and careful monitoring. Some peculiar clinical findings observed in Italian patients point to a genetic heterogeneity of lysinuric protein intolerance.