Synovitis, acne, pustulosis, hyperostosis, osteitis (SAPHO), and chronic recurrent multifocal osteomyelitis (CRMO): A tale of two cases

Abstract

BackgroundSAPHO (Synovitis Acne Pustulosis Hyperostosis Osteitis) and CRMO (Chronic Recurrent Multifocal Osteomyelitis) are chronic relapsing osteoarticular disorders with common dermatological manifestations. Aim of the workTo describe a case of SAPHO in an adult and CRMO in a child. Cases presentationCase 1: A 32-year old man presented with dull aching low back pain for 2 years with morning pain/stiffness. On examination there were acneform lesions on the face, tenderness over thoracic spine and swelling of left sternoclavicular joint. Plain x-rays showed sclerosis/widening/irregularity of sternoclavicular joint, sclerosis/irregularity of endplate, loss of disc space with syndesmophytes in mid/lower dorsal spine (D6-11) and sclerosis in middle of left tibia. Magnetic resonance imaging (MRI) spine showed cortical erosions and marrow edema (D6-L1) with findings suggestive of aseptic/inflammatory spondylodiscitis. A bone scan showed increased uptake D7-D12 and mid-third tibia (hyperostosis). Biopsy from D6/D7 showed normal histopathology. Case 2: A 10-year-old girl presented with pain/swelling of right foot for 2 months, pain/swelling of left shoulder and sternoclavicular joint with pustular acne on the face. There was swelling/tenderness over right 5th metatarsal base and left sternoclavicular joint as well as tenderness over proximal humerus. ESR was 65 mm/1sthr. Plain x-rays showed punched-out lytic lesions surrounded by sclerosis in metatarsal base and metaphysis of humerus. Patient was diagnosed as CRMO. ConclusionSAPHO and CRMO are rare and their diagnosis is sometimes not easy. SAPHO can present as aseptic spondylodiscitis. Both conditions can be diagnosed with clinical and radiological features. A biopsy is necessary for ruling out other conditions.