Systemic Disorders

Question 1

Management and diagnostic strategies for Duchene muscular dystrophy

Answer 1

Duchenne muscular dystrophy (DMD) is caused by a defective gene located on the X chromosome that is responsible for the production of dystrophin, a high molecular weight protein that is localized to the sarcolemmal membrane of normal skeletal muscle.

DMD causes a primary cardiomyopathy with extensive fibrosis of the posterobasal left ventricular wall, resulting in the characteristic ECG changes of tall right precordial R waves with an increased R/S ratio and deep Q waves in leads I, aVL, and V5-6 . As the cardiac disease progresses, fibrosis can spread to the lateral free wall of the left ventricle. The extent and severity of fibrosis can be assessed by examining the distribution of late gadolinium enhancement with CMR. Significant mitral regurgitation is often present due to involvement of the posteromedial papillary muscle. Cardiac involvement is also associated with conduction abnormalities, especially intraatrial and interatrial but also involving the AV node, and a variety of arrhythmias, primarily supraventricular

Question 2

Treatment of pHTN with Scleoderma

Answer 2

Most aspects (including the indications) of PAH-specific therapy for patients with SSc-PAH are identical to those for patients with other types of PAH. In most cases, patients with World Health Organization (WHO) functional class II and III symptoms (table 4) are typically treated with upfront combination oral therapy (eg, ambrisentan and tadalafil) while those with WHO functional class IV are generally treated with a parenteral prostanoid and a second oral agent from a different class. This strategy is based upon data extrapolated from major PAH trials that included a small proportion of patients with SSc-PAH as well as from observational studies in patients with SSc-PAH.

With the exception of calcium channel blocker (CCB) therapy, agent selection is similar to that in patients with other types of PAH. High-dose CCB therapy is not typically administered since few patients are vasoreactive and even in those who are vasoreactive, a hemodynamic response is rarely sustained. However, low-dose therapy for the treatment of Raynaud phenomenon is appropriate.

Question 3

4F-prothrombin concentrate complex doses for major bleeds and intracranial bleeds

Answer 3

A fixed dose can be given with 1000 units for any bleed and 1500 units for intracranial bleed; therefore, either 1500 units fixed dose or 25 units/kg could be used in this case.

Question 4

Metabolic Syndrome

Answer 4

Any three of the following five criteria:
- abdominal obesity (waist circumference in men ≥102 cm or ≥88 cm in women)
- elevated triglycerides (>175 mg/dL)
- low high-density lipoprotein (<40 mg/dL in men or <50 mg/dL in women)
- elevated BP ≥130/85 mm Hg
- elevated fasting plasma glucose (≥100 mg/dL).