Sarcoidosis Flashcards
Sarcoidosis - Diagnosis: Example Question
You see a new patient in dermatology outpatients clinic. A 65 year-old female has been referred by her GP with a new rash on her anterior shins. You review the past-medical history which includes a left sided Bell’s palsy (poor resolution), a permanent pacemaker for complete heart block and a recent urinary tract infection treated with trimethoprim.
The GP letter describes a new anterior rash bilaterally on her shins that coincided with a viral illness for which the patient was symptomatic with arthralgia and myalgia. The GP letter describes the rash as large round dusky nodules. There is no rash on examination today in clinic.
What is the likely cause of the rash?
Trimethoprim > Sarcoidosis Streptococcal infection Mycoplasma pneumonia Non-Hodgkin's lymphoma
The description of the rash that has now resolved is typical for erythema nodosum. This is a self-resolving eruption that has many possible underlying aetiologies. In this case the likely diagnosis that unifies the symptoms of complete heart block, erythema nodosum and Bell’s palsy is sarcoidosis.
Sarcoidosis - Mx and Indications for Steroids
Sarcoidosis is a multisystem disorder of unknown aetiology characterised by non-caseating granulomas. It is more common in young adults and in people of African descent.
Indications for steroids
- patients with chest x-ray stage 2 or 3 disease who have moderate to severe or progressive symptoms. Patients with asymptomatic and stable stage 2 or 3 disease who have only mildly abnormal lung function do not require treatment
- hypercalcaemia
- eye, heart or neuro involvement
Sarcoidosis - Mx: Example Question
A normally fit and well 32-year-old black woman complains of a fever and tiredness over the past month. Her temperature is 38.2ºC, blood pressure is 115/70 mmHg, pulse is 75/min and respirations are 18/min.
On examination there were multiple non-tender cervical and axillary lymph notes. Lung auscultation reveals fine crackles throughout bilaterally. A chest x-ray film demonstrated hilar lymphadenopathy with diffuse interstitial infiltrates. A subsequent lymph node biopsy showed non-caseating granulomas.
Which of the following is the most appropriate therapy?
Supportive therapy Methotrexate Ciclosporin > Glucocorticoids Infliximab
The patient’s presentation is consistent with sarcoidosis. Characteristically the patient is usually asymptomatic, with disease detection occurring via an abnormal chest x-ray film which demonstrates bilateral symmetric hilar adenopathy usually with para-tracheal adenopathy and/or parenchymal infiltrates. In this case, the patient has reached the threshold for starting steroid treatment. None of the other medications have been shown to be beneficial in treating this grade of sarcoidosis.
Sarcoidosis - Ix
Sarcoidosis: investigation
There is no one diagnostic test for sarcoidosis and hence diagnosis is still largely clinical. ACE levels have a sensitivity of 60% and specificity of 70% and are therefore not reliable in the diagnosis of sarcoidosis although they may have a role in monitoring disease activity. Routine bloods may show hypercalcaemia (seen in 10% if patients) and a raised ESR
A chest x-ray may show the following changes:
stage 0 = normal
stage 1 = bilateral hilar lymphadenopathy (BHL)
stage 2 = BHL + interstitial infiltrates
stage 3 = diffuse interstitial infiltrates only
stage 4 = diffuse fibrosis
SEE PASSMED CT and CXR
Chest x-ray and CT scan showing stage 2 sarcoidosis with both bilateral hilar lymphadenopathy + interstitial infiltrates. The reticulonodular opacities are particularly noted in the upper zones. Remember that pulmonary fibrosis (which this case has not yet progressed to) may be divided into conditions which predominately affect the upper zones and those which predominately affect the lower zones - sarcoidosis is one of the former. The CT of the chest demonstrates diffuse areas of nodularity predominantly in a peribronchial distribution with patchy areas of consolidation particularly in the upper lobes. There is some surrounding ground glass opacities. No gross reticular changes to suggest fibrosis.
Other investigations*
spirometry: may show a restrictive defect
tissue biopsy: non-caseating granulomas
gallium-67 scan - not used routinely
*the Kveim test (where part of the spleen from a patient with known sarcoidosis is injected under the skin) is no longer performed due to concerns about cross-infection
CXR - Stages of Sarcoidosis
A chest x-ray may show the following changes:
stage 0 = normal
stage 1 = bilateral hilar lymphadenopathy (BHL)
stage 2 = BHL + interstitial infiltrates
stage 3 = diffuse interstitial infiltrates only
stage 4 = diffuse fibrosis
Sarcoidosis - Example Presentation
Heart: Complete heart block
Skin: Erythema nodosum
Neuro: Bell’s palsy
