Cutaneous Mycobacterium abscessus infection following hair transplant.

A 28-year-old man presented with a 10-day history of scalp nodules. He had undergone hair transplantation 2 months previously. Incision and drainage of one of the nodules yielded gelatinous material, which was sent for microscopy and culture, including low-temperature culture. After 2 weeks of incubation, culture of the nodule yielded acid- and alcohol-fast bacilli, which were identified as Mycobacterium abscessus, a rapidly growing, nontuberculous mycobacterium, which has been reported to cause cutaneous, soft tissue and respiratory infections following trauma, surgery or injection with nonsterile needles. A high index of suspicion is therefore needed in patients who present with cutaneous infections after cosmetic dermatological procedures, including hair transplantation.

Excision biopsy in a patient with suspected local anaesthetic allergy: use of 0.9% saline with benzyl alcohol as local anaesthesia.

Dermatologists may see patients with actual or suspected local anaesthetic (LA) allergy who require an urgent dermatological procedure to be performed without time for formal allergy testing. We report a case of shave biopsy and subsequent excision biopsy of an atypical naevus performed using tumescent analgesia with 0.9% saline containing benzyl alcohol preservative. The tumescence itself and the benzyl alcohol present in the 0.9% saline solution provided sufficient analgesia for excision. This technique may be an option for managing urgent procedures in patients suspected or known to have allergy to LA.

Neurogenic influences on contralateral responses during experimental rat monoarthritis.

Many inflammatory conditions show topographically precise symmetrical responses. In this study we assessed vascular and cellular responses of apparently normal knees following induction of monoarthritis on the opposite side. A strictly localised monoarthritis was induced in the right knee of experimental animals using intra-articular latex spheres. In both knee joints bradykinin-induced plasma extravasation was significantly enhanced increasing from 0.52 +/- 0.07 micrograms/ml Evans blue to 0.99 +/- 0.07 micrograms/ml and 0.88 +/- 0.1 micrograms/ml in the injected and uninjected, contralateral, knees respectively (P < 0.05). A bilateral increase in cellularity was also apparent with cell counts in the uninjected, and apparently normal, knee increasing from 512 +/- 42 cells/mm2 to a maximum of 812 +/- 125 cells/mm2 on day 10 (P < 0.05). Immunohistological analysis demonstrated that the infiltrating cells in both the ipsilateral and contralateral joints were predominantly macrophages. Cell counts were not increased in the other peripheral joints. Levels of the sensory neuropeptide substance P were significantly elevated in both the ipsilateral and contralateral dorsal root ganglia and prior inhibition of small unmyelinated nerve activity inhibited the cellular infiltrate on the contralateral side, suggesting that the effect was mediated, at least partially, by a specific neurogenic pathway. The data suggests the presence of a neurogenic mechanism able to induce a topographically precise response. This may serve to upregulate the cellular defences of at-risk tissues following a potentially damaging stimulus at another site.

Assessment of cutaneous sensory and autonomic axon reflexes in rheumatoid arthritis.

OBJECTIVE: To assess sensory function in skin overlying the joints of patients with rheumatoid arthritis, in relation to the pain and tenderness which commonly arises in structures not directly involved in the inflammatory process. METHODS: An intradermal injection of capsaicin 0.05 microgram in 10 microliters was made over the wrists and forearms of 40 patients with rheumatoid arthritis and 46 control subjects. Axon reflex vasodilatation was measured using laser Doppler flowmetry. Cholinergic sympathetic function was assessed by measuring axon reflex sweating induced by a single intradermal injection of nicotine 0.5 microgram in 0.1 ml. RESULTS: Capsaicin induced axon reflex vasodilation over the wrists was found to decrease with age in normal subjects (r = -0.62, p < 0.001). In patients with rheumatoid arthritis, capsaicin induced axon reflex vasodilatation was significantly greater over the wrists, but not the forearms, when compared with age matched normal controls (p < 0.01). A minimal correlation between axon reflex vasodilatation and visual analogue pain score was apparent in the rheumatoid group (r = -0.37, p < 0.05). Nicotine induced sweating responses were similar in the rheumatoid and normal groups, and both showed a linear age related decline. CONCLUSIONS: The results show a selective increase of capsaicin induced vasodilatation in skin overlying joints in patients with rheumatoid arthritis. This suggests that the activity of a sub-population of periarticular small sensory fibres is altered, which may explain, at least in part, some of the clinical findings in this disorder.

Can we safely diagnose pigmented lesions from stored video images? A diagnostic comparison between clinical examination and stored video images of pigmented lesions removed for histology.

Rapid expansion of communication technology has permitted the clinician to perform a consultation with a patient located at a different site. Assuming adequate diagnostic accuracy, it could theoretically be possible to use telemedical techniques as a triage tool. Images of pigmented lesions sent by the primary care physician could be viewed by the consultant dermatologist, and those with banal lesions spared from attending clinic. Previous studies assessing diagnostic accuracy of images of lesions have used 'face-to-face' diagnoses as the 'gold standard'. We set out to compare diagnostic accuracy of image examination compared with that of clinical examination, using histological examination as the diagnostic benchmark. We found that pigmented lesions may be diagnosed as accurately by stored video image evaluation as by conventional clinical examination. None of the malignant skin tumours was misdiagnosed as benign in either group. Whilst these results are encouraging in terms of the clinical safety of store-and-forward imaging, the inability to examine the whole patient or to palpate the lesions may limit the acceptability of the technique severely. Further evaluation of the cost : benefit ratio of such a system to the health care provider must be undertaken before considering this technique as a potential adjunct to managing outpatient referrals.

Intra-articular pressure changes in rheumatoid and normal peripheral joints.

OBJECTIVE: To investigate the intraarticular pressure (IAP) dynamics of a spectrum of joints in rheumatoid and normal subjects in order to determine whether a reperfusion event is likely to occur at these sites. METHODS: IAP was measured in the metacarpophalangeal (MCP) (n = 8), wrist (n = 8), ankle (n = 4), and elbow joints (n = 4) of rheumatoid subjects, in addition to the MCP (n = 8), wrist (n = 6), and ankle joints (n = 1) of normal healthy controls, using the hand held portable 295-1 Intra-Compartmental Pressure Monitor System (Stryker, UK). RESULTS: Resting IAP was positive in all rheumatoid joints, and subatmospheric or weakly atmospheric in normal subjects (p < 0.01). Exercise produced an increase in IAP in rheumatoid subjects only (p < 0.01). The addition of saline to normal joints mimicked the IAP changes seen in the rheumatoid group. CONCLUSION: These observations suggest that increased resting IAP is a marker for chronic joint inflammation. The IAP increase seen in the rheumatoid group during exercise supports the concept of hypoxic reperfusion mediated joint injury.