Rheumatology: Fibromyalgia

Fibromyalgia AKA fibromyalgic syndrome (FMS) is one of the most common causes of chronic pain. It is characterised by allodynia, hyperalgesia and a wide range of other symptoms.
On average a FMS patient will have seen three or four different doctors before being diagnosed (taking an average of 2-3 years)!

Epidemiology
Prevalence 2-4%
Female (9:1)
35-60yrs (working age)
increased incidence in patients with autoimmune disorders

Symptoms/Signs
Widespread pain with tender points (pain elicited with palpation of these specific points)
Fatigue (doesn't improve with rest, number one complaint after pain)
Morning stiffness
Sleep disturbances (pt sleeps well but wakes up more tired)
variety of other disturbances; Headaches (tension-type and migraine), paresthesias, trouble concentrating, variable bowel habits, depression, mood and affective disorders, temporomandibular joint syndrome,  idiopathic back pain, non cardiac chest pain, vestibular complaints, ENT symptoms...

Diagnosis
Diagnosis is entirely clinical, by exclusion generally.
Rule out differentials, be vigilant of common co-existing conditions like irritable bowel syndrome
ACR 2010 diagnostic criteria
Reasonable diagnosis:
>Chronic widespread pain for greater than 3 months
>pain at 10 or more tender points (see image linked for specific locations, there are 18 defined areas)
(> also aiding in diagnosis; presence of Fatigue/stiffness and sleep disturbances)

Treatment
Centred towards the pain, but be aware that many FMS patients have concomitant psychiatric problems, so psychiatry referral suggested. Reassure patient its a physical diagnosis and warn them in some cases the symptoms will never resolve completely.

>Non pharmacological treatment
Exercise, CBT, homeopathy, physiotherapy, acupuncture, diet changes, relaxation techniques
all safe in the long term and may have potential benefits (small % of acupuncture pts had increased pain though)
Graded exercise showed benefits in many patients

>Pharmacological treatment
simple analgesics, tramadol,
tricyclic antidepressants
serotonin noradrenaline reuptake inhibitors (SNRIs)
alpha2 agonists (gabapentin, pregabalin)

Differential dx
Chronic fatigue syndrome (fatigue much more prevalent and severe, more an issue than pain)
Multiple bursitis/tendonitis (good response to local inection treatment, tender points absent)
Rheamatoid arthritis/Osteoarthritis (joint swelling, hands affected)
SLE (rash, systemic sx, ANA)
Ankylosing spondylitis (young male, lower back pain)
Polymyalgia rheumatica (older pt, acute onset, steroid responsive)
Hypothyroidism (weight gain, goitre)
Myositis (weakness more than pain)

Random pearls

• Although the etiology is unknown it is believed to be a central sensitization disorder, fitting in with the considerable overlap of IBS and dysmenorrhea with FM. A kind of abnormal response of the nervous system.
• RA and SLE often present as well. 
• FMS is increased in patients that have suffered a physical of psychiatric trauma (perhaps a starting point of the disease)
• increase in metabolic syndrome in FMS patients
• There are three subgroups to further classify FMS patients based on pain control, tenderness and associated symptoms
• In USMLE exam 'steroids' or 'NSAIDS' will not be the correct answer answer to treatment options
• 12th May is Fibromyalgia awareness day
• One third of FMS patients experience major depression or significant anxiety. 

Resources and Sources:
Medscape Fibromyalgia
Paul Bolin CRASH USMLE video on Fibromyalgia
ArthritisUK Great site for patients
More detailed look at diagnostic criteria

 #MEDed #FOAMed #Fibromyalgia #Rheumatology #Chronicpain #widespreadpain