It can also be caused by damage to the lymphatic system from infections such as cellulitis.Primary lymphedema may be congenital or arise sporadically. Multiple syndromes are associated with primary lymphedema, including Turner syndrome, Milroys disease, and Klippel-Trenaunay-Weber syndrome. It is generally thought to occur as a result of absent or malformed lymph nodes and/or lymphatic channels. Lymphedema may be present at birth, develop at the onset of puberty (praecox), or not become apparent for many years into adulthood (tarda). In men, lower-limb primary lymphedema is most common, occurring in one or both legs. Some cases of lymphedema may be associated with other vascular abnormalities.Secondary lymphedema affects both men and women. In women, it is most prevalent in the upper limbs after breast cancer surgery, in particular after axillary lymph node dissection, occurring in the arm on the side of the body in which the surgery is performed. Breast and trunk lymphedema can also occur but go unrecognised as there is swelling in the area after surgery, and its symptoms (peau dorange and/or an inverted nipple) can be confused with post surgery fat necrosis. In Western countries, secondary lymphedema is most commonly due to cancer treatment. Between 38 and 89% of breast cancer patients have lymphedema due to axillary lymph node dissection and/or radiation. Unilateral lymphedema occurs in up to 41% of patients after gynecologic cancer.
Persistent fetal circulation is a condition caused by a failure in the systemic circulation and pulmonary circulation to convert from the antenatal circulation pattern to the "normal" pattern. Infants experience a high mean arterial pulmonary artery pressure and a high afterload at the right ventricle. This means that the heart is working against higher pressures, which makes it more difficult for the heart to pump blood.In a fetus, there is high pulmonary vascular resistance (PVR) and low pulmonary blood flow as the fetus does not use the lungs for oxygen transfer, but instead relies on the placenta for oxygen. When the baby is born, the lungs are needed for oxygen transfer and need high blood flow which is encouraged by low PVR. The failure of the circulatory system of the newborn to adapt to these changes by lowering PVR leads to persistent fetal circulation. The newborn is therefore born with elevated PVR, which leads to pulmonary hypertension. Because of this, the condition is also widely known as persistent pulmonary hypertension of the newborn (PPHN). This condition can be either acute or chronic, and is associated with significant morbidity and mortality. Presentation
Complications
PPHN can range from mild to severe disease. In the most severe form, infants experience severe hypoxemia resulting in cardiac and pulmonary complications.