Antonio is 76 years old. He comes in because of a small bump that appeared on his left ear three months ago. He did not think much of it until something as ordinary as resting his ear on the pillow at night became painful.
The lesion also hurts when we examine and palpate it.
An attached tick should be removed as soon as possible. However, finding a tick does not mean that someone has Lyme disease and does not, by itself, justify prescribing antibiotics. Here are six practical questions on how to prevent, recognise and manage these situations.
.JPG)
|
| Digital myxoid cyst located close to the proximal nail fold. The longitudinal alteration of the nail plate secondary to involvement of the nail matrix can be seen. |
A digital myxoid cyst, also known as a digital mucous cyst or digital myxoid pseudocyst, is a benign lesion that usually develops near the distal interphalangeal (DIP) joint and the nail unit.
It is usually less than 1 cm in diameter and presents as a small, smooth, rounded lesion, either skin-coloured or slightly translucent. It is generally asymptomatic, although it may become painful if inflamed or traumatized. Occasionally, it may spontaneously drain clear, viscous and sticky material.
It is more common from the sixth decade of life onwards and has a well-established association with osteoarthritis of the distal interphalangeal joint. In younger patients, repetitive trauma or repeated use of the affected finger may also contribute to its development.
In most cases, these are small ganglion cysts related to the underlying joint, particularly when degenerative joint changes are present.
 |
The nail may provide the clue
This is probably one of the most interesting clinical features of a digital myxoid cyst.
When the lesion is located close to the proximal nail fold, it may compress the nail matrix. Because the matrix is responsible for producing the nail plate, sustained pressure on a small area may alter nail growth.
The result may be a longitudinal depression or groove in the nail plate, producing true canaliform nail dystrophy. In some patients, this nail change may be more noticeable than the cyst itself.
In most cases, no. Diagnosis is usually clinical, based on the combination of the characteristic morphology and location.
When the lesion is subungual, has an atypical appearance or there is diagnostic uncertainty, imaging may be useful and, occasionally, a biopsy may be required.
An X-ray may be useful when assessing for osteoarthritis or osteophytes of the distal interphalangeal joint, although it is not routinely required.
No. A small, asymptomatic cyst can simply be observed.
Treatment may be considered when there is pain, recurrent inflammation or drainage, thinning of the overlying skin, significant nail deformity, or functional or cosmetic impairment.
| Option | Main advantage | Limitation |
|---|---|---|
| Observation | Appropriate for asymptomatic lesions. Avoids unnecessary procedures. | The cyst may persist or recur. |
| Drainage + compression therapy | Simple and minimally invasive. Sustained pressure may promote collapse of the cyst, fibrosis and reduce refilling after drainage. | Recurrence may occur, and the available evidence is more limited than for surgery. |
| Cryotherapy | A relatively simple outpatient procedure. | Risk of recurrence and local tissue injury. |
| Sclerotherapy | A non-surgical alternative with a good response rate. | May cause pain, inflammation and recurrence. |
| Surgery | It has the highest cure rate; systematic reviews report rates approaching 95%. | Risk of scarring, stiffness, pain or infection. |
The main disadvantage of conservative procedures is recurrence. Surgery has the highest cure rate, particularly when the lesion is adequately treated and, when appropriate, associated joint changes are addressed.
British Association of Dermatologists. Digital myxoid cysts. Updated September 2024. British Association of Dermatologists .
Jabbour S, Kechichian E, Haber R, Tomb R, Nasr M. Management of digital mucous cysts: a systematic review and treatment algorithm. International Journal of Dermatology. 2017;56:701-708. PubMed .
Laulan J, Chammas M. Digital mucous cyst. Hand Surgery & Rehabilitation. 2024. PubMed .
DermNet NZ. Digital myxoid pseudocyst. DermNet .
Paronychia is inflammation of the tissues surrounding the nail and one of the most common nail disorders. Although different forms may look similar at first, distinguishing acute paronychia from chronic paronychia is essential because their mechanisms and treatment are different.
This blog was created to present common clinical situations encountered in general practice in an accessible, practical and engaging way. It includes both clinical cases involving frequently seen conditions and the questions or uncertainties that often arise when assessing and treating a patient.
Its aim is to serve as a helpful resource for everyday clinical practice. The topics are drawn directly from routine consultations and do not follow a predetermined order, reflecting the way patients —and the questions they bring— arrive in the consulting room.
Our intention is to move away from overly academic discussions and to avoid focusing on rare or particularly complex conditions, for which referral to a dermatology specialist remains an appropriate option.
We hope this blog will be useful to both general practitioners and medical students.
In patients with several previous skin cancers, nicotinamide may be used as an additional measure to reduce the development of new tumours. It does not replace photoprotection, treatment of actinic keratoses or dermatological follow-up.
Practical answer. Oral nicotinamide 500 mg every 12 hours may be offered to immunocompetent patients with a history of two or more cutaneous squamous cell carcinomas. The benefit is maintained while treatment is continued. I would not routinely recommend it in solid-organ transplant recipients.
The best-studied profile is a patient who is:
The strongest evidence comes from patients without immunosuppression.
Particularly if they have had two or more cutaneous squamous cell carcinomas in recent years.
Extensive photodamage, numerous actinic keratoses or repeated development of new carcinomas.
This is not primary prevention. There is insufficient evidence to recommend it generally to anyone with photodamage or isolated actinic keratoses who has never had skin cancer.
In the ONTRAC trial, 386 high-risk patients received nicotinamide 500 mg every 12 hours or placebo for 12 months. Nicotinamide reduced the development of new cutaneous squamous cell carcinomas by approximately 30%.
The important nuance: the effect disappeared after treatment was stopped. It should therefore not be presented as a one-year intervention that provides permanent protection.
It is generally well tolerated. The most common adverse effects are gastrointestinal and usually improve after dose reduction or discontinuation.
At the dose used for chemoprevention, specific laboratory monitoring is not usually required.
The main evidence covers 12 months. The optimal duration beyond this period is not well defined.
In solid-organ transplant recipients, the ONTRANS trial included 158 patients and found no reduction in new keratinocyte cancers, cutaneous squamous cell carcinomas, basal cell carcinomas or actinic keratoses with nicotinamide 500 mg every 12 hours for 12 months.
Practical conclusion: do not use nicotinamide as a standard chemoprevention strategy in transplant recipients. The lack of recommendation is mainly due to the absence of a demonstrated clinical benefit, rather than major toxicity concerns.
| Situation | Practical approach |
|---|---|
| Immunocompetent patient with 2 or more previous carcinomas | Consider nicotinamide 500 mg every 12 hours as an additional measure. |
| Photodamage or actinic keratoses only, with no previous skin cancer | Do not recommend it routinely. |
| Solid-organ transplant recipient | Do not use it routinely; prioritise specialist follow-up and other preventive strategies. |
| Patient who stops treatment | Explain that the preventive benefit is not maintained after discontinuation. |
Nicotinamide 500 mg every 12 hours is a simple and well-tolerated option for secondary prevention in immunocompetent patients with two or more previous cutaneous squamous cell carcinomas. It may reduce the development of new cutaneous squamous cell carcinomas while treatment is continued. It does not replace standard preventive measures and should not be used routinely in transplant recipients.
Content intended for healthcare professionals. Individualise the indication and always maintain photoprotection, treatment of precursor lesions and clinical follow-up.
A 52-year-old patient has had facial lesions for about eight months; they began as small papules and pustules.
The patient had tried several topical treatments, but obtained only temporary relief with a cream containing clobetasol 0.05%, initially prescribed for a foot problem. They have been applying it daily to the face for three months.
Despite this, the condition continues to worsen and is accompanied by an intense burning sensation.
 |
Diagnosis: steroid-induced rosacea-like dermatitis or steroid rosacea.
Prolonged application of potent topical corticosteroids to the face can cause a condition that mimics or worsens rosacea.
It may present with persistent erythema, burning, flushing, papules, pustules, or inflammatory plaques. In some patients, it follows a predominantly perioral, periocular, or perinasal pattern.
The corticosteroid initially reduces inflammation and provides rapid improvement. However, continued use leads to dependence, loss of efficacy, and progressive worsening.
Key point: the immediate relief produced by the corticosteroid may conceal the fact that, in the medium term, it is perpetuating and worsening the condition.
The corticosteroid rapidly reduces erythema and the burning sensation.
When its use is reduced or stopped, vasodilation, burning, and a severe inflammatory flare develop.
The patient uses it again to relieve the flare, establishing a cycle of dependence.
| Clinical feature | What it suggests |
|---|---|
| Use of a potent corticosteroid on the face | This is the key history finding. |
| Rapid but temporary improvement | Encourages the patient to continue applying it. |
| Erythema, papules, and pustules | Produces an appearance similar to inflammatory rosacea. |
| Intense burning or stinging | Common, especially during the rebound effect. |
| Worsening after discontinuation | Suggests corticosteroid-induced dependence and rebound. |
In any rosacea-like facial eruption, always ask what products the patient is applying and for which areas they were originally prescribed.
Review creams, ointments, and treatments used in recent months.
Link onset or worsening to facial corticosteroid use.
Explain that temporary worsening may occur during withdrawal.
The essential measure is to withdraw the topical corticosteroid. However, after prolonged use, abrupt discontinuation can trigger a very severe flare and prompt the patient to apply it again.
Potent topical corticosteroids should not be used continuously on the face. They may provide initial improvement, but can also cause dependence, rebound, and progressively more severe rosacea-like dermatitis.
When rosacea improves briefly with corticosteroids but subsequently worsens, consider steroid rosacea.
Clinical presentation Easy. Common. Antonio is 76 years old. He comes in because of a small bump that appeared on his le...
