Myocarditis, also known as inflammatory cardiomyopathy, is an acquired cardiomyopathy due to inflammation of the heart muscle. Symptoms can include shortness of breath, chest pain, decreased ability to exercise, and an irregular heartbeat. The duration of problems can vary from hours to months. Complications may include heart failure due to dilated cardiomyopathy or cardiac arrest.Myocarditis is most often due to a viral infection. Other causes include bacterial infections, certain medications, toxins and autoimmune disorders. A diagnosis may be supported by an electrocardiogram (ECG), increased troponin, heart MRI, and occasionally a heart biopsy. An ultrasound of the heart is important to rule out other potential causes such as heart valve problems.Treatment depends on both the severity and the cause. Medications such as ACE inhibitors, beta blockers, and diuretics are often used. A period of no exercise is typically recommended during recovery. Corticosteroids or intravenous immunoglobulin (IVIG) may be useful in certain cases. In severe cases an implantable cardiac defibrillator or heart transplant may be recommended.In 2013, about 1.5 million cases of acute myocarditis occurred. While people of all ages are affected, the young are most often affected. It is slightly more common in males than females. Most cases are mild. In 2015 cardiomyopathy, including myocarditis, resulted in 354,000 deaths up from 294,000 in 1990. The initial descriptions of the condition are from the mid-1800s.
It may develop several days or weeks later in premature babies.The rash has a variable appearance, ranging from a few blotchy red spots to many yellow-white bumps and boils. The classic presentation is 1–3 mm, firm, yellow-white bumps with a surrounding red halo. The rash is often described as "flea-bitten." There may be only a few or many lesions, and they may be clustered or widespread. The rash often appears on the cheeks first and may later spread throughout the face, trunk, arms, and legs. Lesions most often appear on the thighs, buttocks, and trunk. The palms and soles are not affected, likely because the skin in these areas does not have hair follicles.Individual lesions may grow and shrink over hours or days. They usually fade within a week or two. The rash may recur within the next few weeks, but this is rare. Cause
Erythema toxicum neonatorum is related to activation of the immune system, but its exact cause is unknown. Many inflammatory factors have been detected in erythema toxicum neonatorum lesions, including IL-1alpha, IL-1beta, IL-8, and eotaxin. These molecules cause redness and swelling in the skin and attract immune cells.Eosinophils and other immune cells are found in the upper layer of the skin in erythema toxicum neonatorum lesions. Immune cells tend to cluster around hair follicles in particular. The leading hypothesis about the cause of erythema toxicum neonatorum is that bacteria activate the immune system when they enter hair follicles for the first time.