This method of evaluating mitral stenosis tends to overestimate the degree of mitral stenosis, however, because of the time lag in the pressure tracings seen on the right-heart catheterization and the slow Y descent seen on the wedge tracings. If a trans-septal puncture is made during right heart catheterization, however, the pressure gradient can accurately quantify the severity of mitral stenosis. Other techniques
Chest X-ray may also assist in diagnosis, showing left atrial enlargement.Electrocardiography may show P mitrale, that is, broad, notched P waves in several or many leads with a prominent late negative component to the P wave in lead V1, and may also be seen in mitral regurgitation, and, potentially, any cause of overload of the left atrium. Thus, P-sinistrocardiale may be a more appropriate term. Treatment
Treatment is not necessary in asymptomatic patients.The treatment options for mitral stenosis include mitral valve replacement by surgery, and percutaneous mitral valvuloplasty by balloon catheter.The indication for invasive treatment with either a mitral valve replacement or valvuloplasty is NYHA functional class III or IV symptoms.Another option is balloon dilatation. To determine which patients would benefit from percutaneous balloon mitral valvuloplasty, a scoring system has been developed. Scoring is based on 4 echocardiographic criteria: leaflet mobility, leaflet thickening, subvalvular thickening, and calcification. Individuals with a score of ≥ 8 tended to have suboptimal results.
An allergic transfusion reaction is when a blood transfusion results in allergic reaction. It is among the most common transfusion reactions to occur. Reported rates depend on the degree of active surveillance versus passing reporting to the blood bank. Overall, they are estimated to complicate up to 3% of all transfusions. The incidence of allergic transfusion reactions is associated with the amount of plasma in the product. More than 90% of these reactions occur during transfusion. Signs and symptoms
Cause
Allergic reactions from blood transfusion may occur from the presence of allergy-causing antigens within the donors blood, or transfusion of antibodies from a donor who has allergies, followed by antigen exposure.An allergic transfusion reaction is a type of transfusion reaction that is defined according to the Center for Disease Control (CDC)  as:

Diagnosis
An allergic transfusion reaction is diagnosed if two or more of the following occur within 4 hours of cessation of transfusion:

A probable diagnosis results if any one of the following occurring within 4 hours of cessation of transfusion:
The UK hemovigilance reporting system (SHOT), has classified allergic reactions in to mild, moderate and severe. Reactions can occur that have features of both allergic and febrile reactions. Mild
A rash, urticaria, or flushing

Moderate
Wheeze (bronchospasm) or angioedema but blood pressure normal and no respiratory compromise. There may or may not be an associated rash or urticaria. Severe
This can be due to:
Severe breathing problems (Bronchospasm, stridor), angioedema, or circulatory problems (e.g. hypotension) which require immediate medical treatment OR admission to hospital OR lengthens the duration of hospital admission.