Characteristic findings in Guillain–Barré syndrome are an elevated protein level, usually greater than 0.55 g/L, and fewer than 10 white blood cells per cubic millimeter of fluid ("albuminocytological dissociation"). This pattern distinguishes Guillain–Barré syndrome from other conditions (such as lymphoma and poliomyelitis) in which both the protein and the cell count are elevated. Elevated CSF protein levels are found in approximately 50% of patients in the first 3 days after onset of weakness, which increases to 80% after the first week.Repeating the lumbar puncture during the disease course is not recommended. The protein levels may rise after treatment has been administered. Neurophysiology
Directly assessing nerve conduction of electrical impulses can exclude other causes of acute muscle weakness, as well as distinguish the different types of Guillain–Barré syndrome. Needle electromyography (EMG) and nerve conduction studies may be performed. In the first two weeks, these investigations may not show any abnormality. Neurophysiology studies are not required for the diagnosis.Formal criteria exist for each of the main subtypes of Guillain–Barré syndrome (AIDP and AMAN/AMSAN, see below), but these may misclassify some cases (particularly where there is reversible conduction failure) and therefore changes to these criteria have been proposed. Sometimes, repeated testing may be helpful. Clinical subtypes
A number of subtypes of Guillain–Barré syndrome are recognized. Despite this, many people have overlapping symptoms that can make the classification difficult in individual cases. All types have partial forms.
Interrupted aortic arch is a very rare heart defect (affecting 3 per million live births) in which the aorta is not completely developed. There is a gap between the ascending and descending thoracic aorta. In a sense it is the complete form of a coarctation of the aorta. Almost all patients also have other cardiac anomalies, including a ventricular septal defect (VSD), aorto-pulmonary window, and truncus arteriosus. There are three types of interrupted aortic arch, with type B being the most common. Interrupted aortic arch (especially Type B) is often associated with DiGeorge syndrome. Signs and symptoms
Patients with an interrupted aortic arch usually have symptoms from birth, with nearly all presenting symptoms within two weeks (when the ductus arteriosus is usually closed). Causes
It is thought that an interrupted aortic arch occurs through excessive apoptosis in the developing, embryonic aorta. Around 50% of patients have DiGeorge syndrome. Diagnosis
It can be diagnosed with a standard echocardiogram. An echocardiogram can also aid in classifying the type of defect. The diagnosis can also be made prior to birth via ultrasound. Patients will have a loss of appetite, appear tired and weak, and exhibit rapid breathing and a rapid heart rate. If the condition progresses, the infant may turn pale, feel cold in the lower half of the body, and have a weak pulse due to insufficient blood flow.