Sarcoidosis patients with acute arthritis often also have bilateral hilar lymphadenopathy and erythema nodosum. These three associated syndromes often occur together in Löfgren syndrome. The arthritis symptoms of Löfgren syndrome occur most frequently in the ankles, followed by the knees, wrists, elbows, and metacarpophalangeal joints. Usually, true arthritis is not present, but instead, periarthritis appears as a swelling in the soft tissue around the joints that can be seen by ultrasonographic methods. These joint symptoms tend to precede or occur at the same time as erythema nodosum develops. Even when erythema nodosum is absent, it is believed that the combination of hilar lymphadenopathy and ankle periarthritis can be considered as a variant of Löfgren syndrome.Enthesitis also occurs in about one-third of patients with acute sarcoid arthritis, mainly affecting the Achilles tendon and heels. Soft-tissue swelling of the ankles can be prominent, and biopsy of this soft tissue reveals no granulomas, but does show panniculitis similar to erythema nodosum.Chronic sarcoid arthritis usually occurs in the setting of more diffuse organ involvement. The ankles, knees, wrists, elbows, and hands may all be affected in the chronic form and often this presents itself in a polyarticular pattern. Dactylitis similar to that seen in psoriatic arthritis, that is associated with pain, swelling, overlying skin erythema, and underlying bony changes may also occur. Development of Jaccoud arthropathy (a nonerosive deformity) is very rarely seen.Bone involvement in sarcoidosis has been reported in 1–13% of cases.
Homatropine (Equipin, Isopto Homatropine) is an anticholinergic medication that is an antagonist at muscarinic acetylcholine receptors and thus the parasympathetic nervous system. It is used in eye drops as a cycloplegic (to temporarily paralyze accommodation), and as a mydriatic (to dilate the pupil). The related chemical compound homatropine methylbromide (methylhomatropine) is a different medication. Homatropine is less potent than atropine and has a shorter duration of action. It is available as the hydrobromide salt. Homatropine is also given as an atropine substitute given to reverse the muscarinic and CNS effects associated with indirect cholinomimetic (anti-AChase) administration. It is on the World Health Organizations List of Essential Medicines. Side effects
Blurred vision
Sensitivity to light

Contraindications
Untreated glaucoma
Myasthenia gravis
Severe heart failure
Thyrotoxicosis


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