There are a few complications that can result from ongoing inflammation, including those directly related to the formation of granulomas within endocrine glands. They include:

  • Hypercalcaemia (too much calcium in the blood) and Hypercalciuria (too much calcium in urine) – The incidence of hypercalcaemia is estimated to be 10% in sarcoidosis patients, with no association with a specific demographic. The severity depends on many factors, including disease activity, sunlight, and diet variations. Hypercalciuria on the other hand is estimated to be three times more common and seen more often in men than women. If left untreated, elevated levels of calcium in the blood or urine can cause potentially severe complications including bone loss, osteoporosis (week or brittle bones, especially with long-term treatment with steroids), and long-term kidney and pancreas complications. While the mechanism is not fully understood, treatment for high levels of calcium in the blood or urine include corticosteroids (first-line treatment), ketoconazole, chloroquine, hydroxcloroquine, and other drugs, including diuretics. Ongoing monitoring of calcium levels is needed to ensure the condition does not worsen and to ensure any side effects of medications do not cause further complications.
  • Suppressed Parathyroid Hormone (PTH) – PTH is released by four small glands in the neck when vitamin D metabolites and low levels of calcium are detected in the blood. It is responsible for controlling the levels of ionized calcium and fluid in the blood. Elevated levels of calcium in the blood blocks the release of PTH. Since sarcoidosis patients commonly have high levels of calcium in the blood and therefore suppressed release of PTH, physicians should be suspicious that their patient also suffers from hyperthyroidism when PTH levels are high.
  • Vitamin D Dysregulation – Patients who suffer from sarcoidosis often have low levels of vitamin D in their blood, believed to be part of the immune response in the condition. However, there are two forms of vitamin D, the active and inactive forms. In doing routine blood work, many physicians will notice that the levels of the active form of vitamin D are low in sarcoidosis patients. To address this perceived issue, patients are often prescribed a supplement to increase the levels of the active form in their system resulting in kidney stones. In order to appropriately determine if a supplement is needed, the physician needs to run more extensive blood work, measuring both the active and inactive forms of vitamin D. Studies have shown that in the majority of cases, no supplementation is required.

How can sarcoidosis affect the eyes?

  • Cataract Formation – A well recognized complication of uveitis with an estimated 14-30% of patients affected, cateract occurs either as a result of inflammation or treatment with steroids. In general, cataract surgery is the recommended treatment with good outcomes, provided that inflammation is controlled after surgery and there is no permanent damage due to structural abnormalities or glaucoma.
  • Glaucoma – Describing increased pressure within the eyeball due to damage of the optic nerve, this condition can result in gradual loss of sight or total blindness. Treatment with corticosteroids is often to blame. It is recommended that sarcoidosis patients have regular appointment with an ophthalmologist (twice a year) to ensure that sarcoidosis affecting the eye and systemic treatments do not cause complications.

What are parasarcoidosis syndromes?

Many sarcoidosis patients experience complications or symptoms that are not directly related to granulomas or fibrosis. These are called parasarcoidosis syndromes and they can have a significant impact on a patient’s quality of life. The main parasarcoidosis syndromes are fatigue, vitamin d dysregulation, erythema nodosum, small-fiber neuropathy, pain syndromes, depression, and cognitive impairment.


Fatigue affects a large amount of sarcoidosis patients, even when their other symptoms are under control.

Vitamin D Dysregulation

Vitamin D dysregulation is common in sarcoidosis patients. This is a result of the increase in an enzyme that converts the inactive form of vitamin D into the active form. Doctors often misread vitamin D levels in sarcoidosis patients which can lead to hypercalciumia or hypercalciuria.

Erythema Nodosum

Erythema Nodosum is a skin lesion that develops without granuloma formation. Erythema Nodosum occurs in up to 35% of sarcoidosis patients and presents as tender bumps usually on usually on the front of the legs.

Small-Fiber Neuropathy (SFN)

SFN occurs in up to 25% of sarcoidosis patients and can significantly impair a patient’s quality of life. SFN has two sub-categories: painful neuropathy and autonomic neuropathy. Painful neuropathy affects the fibers within the skin that sense heat and pain. This can result in pain, numbness, vibrations or electric shock sensations, and dysesthesias.

Autonomic neuropathy, on the other hand, can cause sweating, anhidrosis, tachycardia, orthostasis, nausea, vomiting, diarrhea, bowel/bladder disturbances, sexual dysfunction, and flushing. Autonomic neuropathy usually happens along with painful neuropathy.

Pain Syndromes

More than 70% of sarcoidosis report experiencing pain. Much of this pain is not directly related to the formation of granulomas. Small-fiber neuropathy (discussed above) is one of the causes of pain in sarcoidosis patients. Muscle pain from coughing also causes chest pain in many sarcoidosis patients. Other possible causes of pain include:

  • Sarcoiliitis
  • Spondyloarthritis
  • Carpal tunnel
  • Psychological and emotional problems
  • Depression
  • Immobility


Between 25% and 60% of sarcoidosis patients report experiencing depression. There is some debate as to whether depression is a parasarcoidosis symptom. Patients may be depressed from a response to the granulomas in their organs, from medication side effects, or from the psychosocial effects of living with a chronic illness.

Cognitive Impairment

Some patients also report cognitive dysfunction ranging from “brain fog” to memory loss.

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