Apart from fibromyalgia
multiple joint pain is seen in hypothyroidism, low
Vitamin D levels, Low Vit B12
levels, anemia, Hashimotos thyroiditis, gout (can sometimes cause multiple joint pain), rheumatoid arthritis, osteoarthritis, SLE, electrolyte disturbance particularly those involving calcium and magnesium, parathyroid gland problems, chondrocalcinosis and chronic fatigue syndrome.