Abstract
Case history
A 67-year-old female presents to her GP with a 3-day history of finger pain and blue/purple discolouration of the right 4th finger (Figure 1). These symptoms have occurred before, but she has not sought help from her GP until now. Her regular medication includes levothyroxine and omeprazole. Past medical history includes hypothyroidism, hiatus hernia and left breast ductal carcinoma-in-situ. A history of drug allergy includes an adverse reaction to nalmefene. The patient is concerned about a possible diagnosis of deep venous thrombosis (DVT) and was expecting investigation with bloods and an electrocardiogram (ECG).
Patient photograph of right 4th finger.
On examination of the finger and hand, her 4th finger has blue/purple discolouration, mainly over the whole digit, not just the palmar side. The finger is tender to touch. The pulse is normal strength and regular in rhythm. There is no right arm oedema. All digits are somewhat cold but with normal capillary refill time.
A spot diagnosis of Achenbach syndrome is made. The patient is advised to take analgesia for symptomatic relief and that the finger pain and discoloration will subside over the next week. The symptoms have resolved completely a week later.
Discussion
Achenbach syndrome, also known as ‘painful blue finger’ or ‘paroxysmal finger haematoma’, is a relatively unknown condition, which results in the sudden onset of bruising with burning pain, mostly on the volar aspects of fingers (Yie, 2019). It was first described by a German physician named Walter Achenbach in 1958 (Achenbach, 1958). The aetiology of Achenbach syndrome is unknown.
Achenbach syndrome most commonly affects middle aged women with a median age of 49.5 years and the most affected anatomical site is the volar aspects of the fingers (Kordzadeh et al., 2016).
The differential diagnoses include (Yie, 2019):
Dermatitis artefacta – Psychocutaneous disorder where injuries are produced by the patient Painful bruising syndrome – Allergic sensitivity to red cells in the tissues Raynaud’s syndrome – Exaggerated vasoconstrictive response of digital arteries in response to the cold Thromboangiitis obliterans (Buerger disease) – Small medium vessel vasculitis associated with smoking
Other differential diagnoses include DVT of the fingers (palmar digital vein). This typically presents with painful, firm blue nodules in one of the flexion creases of the fingers (Kim et al., 2012). Like Raynaud’s syndrome, Achenbach syndrome is also associated with chilblains disease and use of tobacco and alcohol (Carpentier et al., 2016). Acute limb ischaemia is an emergency, typically presenting with some or all of the ‘6 P’s’: Paraesthesia, pallor, perishingly cold, paralysis, pulseless and pain.
Management of Achenbach syndrome is conservative. Investigations can be considered subject to whether any of the differential diagnoses are likely. Thus, occasionally blood tests including full blood count (FBC), erythrocyte sedimentation rate (ESR), prothrombin time (PT), partial thromboplastin time (PTT) and antinuclear antibodies (ANA) may be considered with arterial and venous Doppler ultrasonography for some of the possible diagnoses. However, a spot diagnosis and no investigations are appropriate when the diagnosis of Achenbach syndrome is obvious clinically from the history and examination. Symptomatic relief can be obtained with over-the-counter analgesia. Reassurance should help allay patients’ anxiety. Discolouration usually resolves in 3–6 days without going through the usual stages of a bruise.
Key learning points from this case are the distinctive presenting features of Achenbach syndrome that include a single digit being affected with sparing of the fingertip and nailbed. Prompt spontaneous resolution of symptoms in conjunction with normal laboratory tests is consistent with the diagnosis of Achenbach syndrome.
Achenbach syndrome may be more common than it is thought to be, and this is highlighted in the paper by Carpentier et al. reporting a prevalence of 12.4% in women and 1.2% in men among 802 subjects from three different regions of France (Carpentier et al., 2016). If this prevalence is correct, clinicians working in primary care are likely to encounter this condition and an understanding of Achenbach syndrome may enable reassurance of presenting patients about its benign nature, potentially avoiding unnecessary investigation.
