Does your GP have a copy of the MEA purple book?
Below is section 6.6.2, which includes information on the assessment of adrenal gland function
Dr Charles Shepherd
Hon Medical Adviser, MEA
Website:
www.meassociation.org.uk
6.6.2 Examples of further tests that may be necessary
· Autonomic function tests (e.g. tilt-table testing) and Composite Autonomic Symptom Scale (COMPASS) if autonomic symptoms, syncope or postural hypotension are prominent.
· Chest X-ray if there is a history of chronic cough.
· Infectious disease screen if there is any possibility of chlamydia pneumonia (Chia JK and Chia LY 1999), hepatitis B/C, HIV, Lyme disease, mycoplasma, Q fever, etc.
· MRI scan of brain if multiple sclerosis is considered possible.
· Muscle biopsy if serum creatine kinase is raised or where there is progressive deterioration in muscle strength and/or muscle wasting.
· Rheumatology and autoantibody screen if any degree of arthralgia is prominent. Antinuclear antibody may be positive in people with ME/CFS. If so, consider whether this could be related to systemic lupus erythematosus, especially if the titre is high. If systemic lupus erythematosus is considered to be a possibility, test for antinuclear and anti-double stranded DNA antibodies and complement.
Anti-CCP antibodies are a more sensitive and specific test for early rheumatoid arthritis than rheumatoid factor.
Other infections that can cause an arthralgia and fatigue syndrome include Borrelia, Brucella, Campylobacter, cytomegalovirus, parvovirus, shigella and Yersinia.
· Schirmer’s test if dry eyes – possibility of Sjögren’s syndrome
[SL1] . Some patients with chronic fatigue have dry eyes and mouth and other features suggestive of Sjögren’s syndrome. They should be investigated for inflammatory markers, elevated immunoglobulins and autoantibodies. If Sjögren’s syndrome is excluded, it is still important to provide symptomatic relief for these symptoms. Helpful information is available from Arthritis Research UK.
· Serum 25-hydroxy vitamin D (25-OHD). Consider vitamin D deficiency in adults with restrictive diets and lack of access to sunlight. A retrospective study of serum 25-OHD levels in 221 ME/CFS patients found moderate to severe suboptimal levels with a mean level of 44.4nmol/l (Berkovitz
et al 2009). Vitamin D deficiency often goes unrecognised and can cause bone or muscle pain and muscle weakness. It can co-exist with ME/CFS. Levels < 25nmol/ml may be associated with symptoms.
NB: Low serum calcium and phosphate and an elevated alkaline phosphatase are consistent with osteomalacia.
· Serum estradiol and follicle-stimulating hormone if there is significant premenstrual exacerbation of symptoms (Studd and Panay 1996) or the possibility of an early menopause.
· Serum prolactin and neuroradiology investigations if there are symptoms that could be caused by a pituitary tumour (e.g. headaches, eye problems and symptoms suggestive of prolactin excess such as acne, galactorrhoea, hirsutism, menstrual irregularities, loss of libido) or hypopituitarism (Coucke
et al 2013; Hurel
et al 1995).
· Short synacthen (ACTH) test if plasma or urinary cortisol is low with symptoms (i.e. weight loss, nausea, pigmentation of non-sun exposed areas) and if routine screening tests suggest Addison’s disease (i.e. hypotension, low serum sodium, raised potassium).
The short synacthen test may fail to identify people with ACTH deficiency due to hypothalamic or pituitary disorders. The insulin tolerance test remains the gold standard for diagnosing ACTH deficiency, with the other tests in reserve and to be interpreted in the light of clinical context.
The basal 9am cortisol test is also of contributory value. Cortisol is secreted in a pulsatile manner and has a diurnal variation (a peak in the morning and a trough at night) so measuring cortisol at random gives a poor indication of adrenal function in most cases. Cortisol measured at 9am can be used as a crude indicator. A measurement of > 500nmol/l suggests normal adrenal function, and a measurement of < 165nmol/l suggests adrenal insufficiency. A measurement of < 100nmol/l at 9am is diagnostic of significant deficiency and requires urgent referral.
· Patients with polycystic ovarian syndrome may experience fatigue as part of the metabolic syndrome. The fatigue may be compounded by a raised BMI, which is a common feature.
· An unfavourable lipid profile – increased triglycerides and lowered HDL cholesterol – has been reported in ME/CFS (Tomic
et al 2012).
Additional and helpful info on the cortisol blood test from (UK) lab tests online:
http://labtestsonline.org.uk/understanding/analytes/cortisol/tab/sample/