BACKGROUND Hypophosphatasia (HP) is characterized by a genetic defect in the tissue-nonspecific alkaline phosphatase (TNSALP) gene and predominantly an autosomal recessive trait. HP patients suffer from reduced bone mineralization. Biochemically, elevated concentrations of substrates of TNSALP, including pyridoxal-5'-phosphate and inorganic pyrophosphate occur in serum, tissues and urine. The l...

Chronic recurrent multifocal osteomyelitis (CRMO) is a form of chronic nonbacterial osteitis (CNO) characterized by one or more lytic bone lesions with no identifiable cause1. The metaphyses of long bones and the clavicle are most frequently affected, although any bone may be involved. Most cases begin in childhood, and follow an intermittent course. Pain is the most common presenting symptom. ...

Pyoderma gangrenosum (PG) is an uncommon, chronic ulcerative condition of the skin that was first described in 1930. It can occur in any age group, but only 4% of the patients are infants or children. An underlying systemic disease is present in approximately 50% of the patients with PG. The most common associations include inflammatory bowel disease, arthritis, lymphoproliferative disorders an...

Introduction The cytoplasmic S100 proteins derived from cells of myeloid origin. Calprotectin (MRP8/14 protein complex) might be a biomarker either for autoinflammation and autoimmunopathy. Since autoinflammatory diseases might be a diagnostic challenge calprotectin may be helpful in the diagnosis of autoinflammatory diseases. Chronic nonbacterial osteomyelitis (CNO) is an autoinflammatory, non...