SARCOID
CUTANEOUS MANIFESTATIONS OF SARCOID |
Clinical Findings: Sarcoidosis can occur in any ethnic population, but it is seen at a
higher rate in African Americans. It also has a higher incidence in women. The
usual age at onset is before 40 years. Up to 90% of patients with sarcoid have
a benign clinical course with no increased mortality. Sarcoidosis has been
reported to occur in a familial form, which has led researchers to look for
specific genetic defects that could explain the disease. However, sarcoid
remains an idiopathic multisystem disease. There are many distinct clinical
expressions of the disease that are common enough that they have been named, including
Löfgren’s syndrome, lupus pernio, Darier-Roussy sarcoid, Heerfordt syndrome,
and Mikulicz syndrome.
Sarcoid can affect the skin in a multitude of ways.
There are both specific and nonspecific skin findings. The most common
nonspecific skin finding is erythema nodosum. Erythema nodosum affects the
lower anterior extremities. It manifests as tender subcutaneous nodules or
plaques. Examination of biopsy specimens shows a nonspecific form of
panniculitis. The etiology of erythema nodosum in patients with sarcoid is
poorly understood.
The lesions of sarcoid that occur within the
integumentary system are quite varied. The most common specific skin lesion is
a slightly brownish to red-brown papule, plaque, or nodule with varying amounts
of hyperpigmentation. Sarcoid is a mimicker of many other conditions,
especially in its skin lesions. Macular lesions, ulcerations, subcutaneous
nodules, annular plaques, ichthyosiform erythroderma, and alopecia have all
been described as potential presentations of sarcoid.
The extracutaneous organ system most commonly involved
is the pulmonary system. There is a relatively straightforward classification
that describes the stages of pulmonary sarcoid based on radiographic findings.
The higher the radiographic stage, the more severe the disease. Isolated
bilateral hilar adenopathy is the most common pulmonary finding, and it is the
basis for stage I radiographic disease. These patients are most commonly
asymptomatic, and the adenopathy is found on routine radiographic testing. Any
findings of pulmonary sarcoid should prompt referral of the affected individual
to a pulmonologist for pulmonary function testing.
Löfgren’s syndrome is defined by the acute onset of
erythema nodosum, almost exclusively in young adult women; it is seen in
association with fever, bilateral hilar adenopathy, and uveitis. Other,
non-specific constitutional signs are often present. The erythrocyte sedimentation rate is uniformly elevated.
For some unknown reason, this syndrome is most commonly seen in young Caucasian
women. This form of sarcoidosis typically resolves spontaneously within 2 to 3
years.
Lupus pernio is the name given to the clinical
findings of specific cutaneous sarcoid involvement of the nose and the rest of the face. This form of sarcoid is
quite resistant to therapy, runs a more prolonged course, and is often
difficult to treat. The skin findings are typically shiny brown-red plaques,
papules, and nodules overlying the nose and other regions of the face. The
involvement can become so severe as to cause disfigurement of the nose by shiny
red-brown papules and plaques.
Lupus pernio has nothing to do with the autoimmune disease lupus. Lupus pernio
can be very difficult to treat, and systemic immune suppression is often
required.
Subcutaneous sarcoidosis, also called Darier-Roussy
sarcoid, is an uncommon condition that manifests as subcutaneous plaques of
varying size. This is a rare finding in patients with sarcoid. It manifests as
slightly tender, dermal nodules with an overlying hyperpigmentation or
normal-appearing skin. A biopsy specimen taken from one of the subcutaneous
nodules shows the typical findings of sarcoid.
Heerfordt syndrome is an extremely rare version of
sarcoidosis that manifests more commonly in young adult men than in women. It
is manifested by fever, parotid gland hypertrophy, and lacrimal gland
enlargement in association with facial nerve palsy and uveitis. Neurological
involvement with sarcoidosis may cause papilledema and cerebrospinal fluid
pleocytosis, indicating an inflammatory reaction pattern. Meningism can occur
with headache, spinal stiffness, and photophobia. Mikulicz syndrome is not
specific to sarcoid. It is manifested by bilateral enlargement of various
glands, including the parotid, submandibular, and lacrimal glands. The
tonsillar tissue may also be involved. Fever is common, as is the subsequent
development of dry eyes and mouth due to the widespread, often painless,
inflammation of the affected glands. It has been seen with uveitis and is
considered by some as a variant of Sjögren’s syndrome.
Diagnostic testing to confirm sarcoid includes, most
importantly, a tissue biopsy. Tissue sampling is diagnostic and should lead the
physician to search for other organ systems involved with sarcoidosis.
Laboratory testing may show elevated levels of serum calcium and
angiotensin-converting enzyme. Chest radiographs can identify a spectrum of
disease that is staged by certain criteria. Patients uniquely show a decreased
ability to mount a delayed-type hypersensitivity reaction. This may be
manifested by an inability to react to intradermally placed antigens such as
tuberculin or candida and is termed anergy. Sarcoid patients in the past
were frequently found to have a positive Kveim test. This test is no longer
clinically performed because of the danger of transmitting a bloodborne
pathogen. The test was performed by interdermal placement of a small amount of
a suspension of human spleen and lymph node that had been affected by sarcoid,
similar to the placement of a purified protein derivative (PPD) test for
tuberculosis. This test was found to be positive in more than 85% of patients
with sarcoid.
Mortality is uncommon but may occur secondary to severe cardiac, renal, or pulmonary involvement.
SYSTEMIC MANIFESTATIONS OF SARCOID |
Pathogenesis: The exact
etiology of sarcoidosis is unknown. For years, scientists have been looking at
the potential causative link between sarcoid and an infectious agent, usually
an atypical mycobacterial agent. However, no conclusive evidence has been
reported to indicate that sarcoid is caused by an infectious disease. Histology:
The classic finding of multiple, noncaseating epithelioid granulomas
with a sparse surrounding inflammatory infiltrate is the hallmark of
sarcoidosis.
The granulomatous findings are consistent across all
of the various tissues affected by sarcoid. Many nonspecific histological
findings can also be seen, but not on a consistent basis; these include
Schaumann bodies and asteroid bodies.
Treatment: The treatment
for sarcoid has been consistent over time and includes nonspecific
immunosuppression, most commonly with oral corticosteroids such as prednisone. Isolated cutaneous findings may be
treated with topical corticosteroids or intralesional steroid injections.
Methotrexate is a steroid-sparing agent that is used for difficult-to-control
disease and for lupus pernio. The anti tumor necrosis factor medications, infliximab and adalimumab, have been
used with some success. The use of hydroxychloroquine has also been advocated for treatment of cutaneous sarcoid.