Differential Diagnosis
The patient's symptoms and laboratory results suggest an autoimmune or inflammatory condition. Here's a categorized differential diagnosis:
- Single most likely diagnosis
- Relapsing Polychondritis: The patient's symptoms, including joint hypermobility, tissue laxity, and elevated inflammatory markers, are consistent with relapsing polychondritis, an autoimmune disorder that can be triggered by various factors, including hyaluronidase. The decrease in C3 and C4 levels over the past year also supports this diagnosis.
- Other Likely diagnoses
- Ehlers-Danlos Syndrome (EDS): The sudden onset of joint hypermobility and tissue laxity could be indicative of EDS, a genetic disorder affecting connective tissue. However, the acute phase with elevated ESR and CRP, and the triggering event of hyaluronidase, make this diagnosis less likely.
- Mixed Connective Tissue Disease (MCTD): The patient's symptoms, including muscle pain, joint pain, and elevated inflammatory markers, overlap with MCTD, an autoimmune disorder that combines features of lupus, scleroderma, and rheumatoid arthritis.
- Sjögren's Syndrome: The patient's symptoms, such as joint pain and elevated inflammatory markers, could be consistent with Sjögren's syndrome, an autoimmune disorder that primarily affects the exocrine glands.
- Do Not Miss
- Lupus: Although the patient's symptoms are not typical of lupus, the decrease in C3 and C4 levels, and the elevated inflammatory markers, make it essential to consider this diagnosis, as lupus can be life-threatening if left untreated.
- Scleroderma: The patient's symptoms, including tissue laxity and joint pain, could be indicative of scleroderma, a chronic autoimmune disorder that affects the skin and internal organs.
- Rare diagnoses
- Marfan Syndrome: The patient's sudden onset of joint hypermobility and tissue laxity could be consistent with Marfan syndrome, a genetic disorder affecting connective tissue. However, the absence of other characteristic features, such as ocular or cardiovascular abnormalities, makes this diagnosis less likely.
- Stiff Person Syndrome: The patient's symptoms, including muscle pain and stiffness, could be consistent with stiff person syndrome, a rare autoimmune disorder that affects the central nervous system. However, the lack of other characteristic features, such as progressive stiffness and impaired mobility, makes this diagnosis unlikely.