Abstract
Lysosomal storage diseases (LSD) represent a heterogeneous group of > 60 severe hereditary metabolic disorders due to impaired function of one or more lysosomal enzymes or disorders of protein processing and transport across the lysosomal membrane. The diagnosis of LSD is based on clinical suspicion and the results of enzymatic and molecular analyses.
Of the 836 LSD patients diagnosed in the last 30 years, mucopolysaccharidoses (n = 150), Gaucher disease (n = 57), and Fabry disease (74 hemizygous men and 116 heterozygous women) were the most common. Initial symptoms of LSD that were initially diagnostically non-specific included swelling and limited mobility of large and/or small joints, knee and hip pain, joint disfiguration and bone deformity, hepatomegaly and/or splenomegaly, recurrent upper respiratory tract infections, obstructive and/or restrictive pulmonary disorder, decreased renal function, anemia and, in some types of LSD, growth disorders, craniofacial dysmorphia and cognitive impairment.
Patients went through a number of specialist outpatient clinics including rheumatology, orthopedics, ENT, neurology, nephrology or hematology, which in most cases led to late diagnosis. Although individual types of LSD are rare, many are treatable or at least therapeutically modifiable.
Enzyme replacement therapy (ERT), substrate reducing therapy (SRT), and hematopoietic stem cell transplantation are useful in therapy, which can significantly improve disease prognosis or at least stabilize its progression. Conclusion: The efficacy of treatment in patients with lysosomal storage diseases is significantly dependent on early diagnosis, in which rheumatology specialists should participate as well.