Creatinine Kinase (CK-MB) Learning Flash Card

HIV/ Aids - Flash Cards

Onychomycosis and Diabetes: Patient Case Challenges

Onychomycosis is a common infection that can lead to potentially severe complications in patients who have impaired circulation, peripheral neuropathy, or are immunocompromised. This infection is particularly common in patients with diabetes, many of whom have one or more of these conditions. Onychomycosis treatment reduces risks, but is complicated by the potential for drug-drug interactions between systemic antifungals and the large number of medications often taken by these patients. Several topical therapies are available, including two newer agents that became available in 2014, increasing the potential for individualized treatment selection.

The following case-based activity will test your ability to select appropriate therapies in patients with type 2 diabetes and onychomycosis, while bringing you up to date on risks and management of toenail infections in this vulnerable patient population.

Case :

Albert is a 55-year-old man with type 2 diabetes who presents to your office with thickened, elongated, yellowed toenails (picture shown below). He reports that he first noticed the changes in his toenails about 3 months ago, at which time most of his nails were already involved. Albert was diagnosed with type 2 diabetes 4 years ago, and his blood sugar is currently poorly controlled on metformin alone. He has elevated triglyceride levels for which he is taking a low dose of simvastatin. He is clinically obese, which may have contributed to the fact that he did not notice his toenail infection until it was well entrenched.

On clinical examination, you observe that all of Albert’s toenails are yellow in color and 6 have white lateral streaks. Two nails show involvement extending proximally to the lunula. Several nails, including both great toenails, show subungual hyperkeratosis that is greater than 2 mm thick and two are onycholytic. You estimate that at least 75% of the overall area of Albert’s toenails is infected, with involvement seen in all 10 toenails.

Which of the following clinical characteristics is a risk factor for onychomycosis in patients with diabetes?
A. Female sex
B. Neuropathy
C. Renal dysfunction
D. Younger age

Answer: B. Neuropathy

Discussion: Patients with diabetes can develop peripheral neuropathy, which contributes to the risk of developing onychomycosis, perhaps because this condition impedes proper foot care and allows unrecognized trauma to the nail. 

Men with diabetes are approximately 3 times more likely to develop onychomycosis compared with women with diabetes, and the prevalence of onychomycosis increases with age. Onychomycosis does not seem to be linked to the presence or absence of renal dysfunction in patients with diabetes.

Onychomycosis and Diabetes
Onychomycosis is highly prevalent in patients with diabetes. A North American study of 550 consecutive patients with diabetes found abnormal-appearing toenails in 46% of patients and mycological evidence of onychomycosis in 26% of patients. After adjusting for age, the researchers calculated a 34.9% prevalence in the overall US diabetes population, an estimate that is similar in other studies. Onychomycosis was 2.77 times more likely in patients with diabetes compared with individuals without diabetes. Prevalence in the one-third of patients with type 1 diabetes in this study was lower but still elevated compared with individuals without diabetes, with an odds ratio of 1.69. Onychomycosis was also 3 times more likely in men compared with women with diabetes.

Chilaiditi Sign On Chest X ray

The X ray shown below is of an asymptomatic person. 

Description Of Chilaiditi Sign
Chilaiditi described this normal variant in 1911 where the transverse colon is interposed between the right hemidiaphragm and the liver.
Its prevalence is thought to be 0.025%.

Occasional reports describe patients with Chilaiditi’s syndrome where patients complain of intermittent abdominal pain requiring laparotomy to rule out other causes of peritonism, e.g. perforated ulcer, ruptured appendix.

Atrial Fibrillation - ECG and Learning Questions/Answers

ECG Criteria
• P wave: Absent (P may be replaced by fibrillary f wave).
• Rhythm: Irregularly irregular (R-R interval is irregular). (Atrial rate is very high and ventricular rate is less).

According to the rate, atrial fibrillation may be of 2 types:
• Fast atrial fibrillation: Heart rate >100 beats/min.
• Slow atrial fibrillation: Heart rate <100 beats/min.

Q. What is atrial fibrillation?
Ans. It is an arrhythmia where atria beat rapidly, chaotically and ineffectively, while the ventricles respond at irregular intervals, producing the characteristic irregularly irregular pulse. Any conditions causing raised atrial pressure, increased atrial muscle mass, atrial fibrosis, inflammation and infiltration of the atrium can cause atrial fibrillation.

Q. What are the types of atrial fibrillation?
Ans. There are 3 types of atrial fibrillation:
• Paroxysmal: Discrete self-limiting episodes. May be persistent if underlying disease progresses.
• Persistent: Prolonged episode that can be terminated by electrical or chemical cardioversion.
• Permanent: Sinus rhythm cannot be restored.

Keloid Scars - A Brief Discussion

Keloid scars are tumor like lesions that arise from the connective tissue of a scar and extend beyond the dimensions of the original wound

Predisposing factors

• ethnicity: more common in people with dark skin
• occur more commonly in young adults, rare in the elderly

Pathophysiology: When skin is injured, fibrous tissue, called scar tissue, forms over the wound to repair and protect the injury. In some cases, scar tissue grows excessively, forming smooth, hard growths called keloids. Keloids can be much larger than the original wound.

Common Sites (in order of decreasing frequency):

• sternum, 
• shoulder,
• neck,
• face, 
• extensor surface of limbs, 
• trunk

Keloids should not be confused with hypertrophic scars, which are raised scars that do not grow beyond the boundaries of the original wound.