Hearing loss has been reported and may be related to ear canal atresia or stenosis. Umbilical and inguinal hernias have been reported in a small number of people with ring 18. Unilateral renal hypoplasia and aplasia have both been reported in individuals with ring 18. Hydronephrosis as well as pyelonephritis have also been reported in a few individuals. Cryptorchidism, hypospadias, and micropenis have been seen in males with ring 18, while females have been reported with hypoplastic labia. Foot abnormalities are common within the ring 18 population. Scoliosis as well as pectus excavatum have also been frequently reported. Several people with ring 18 have growth hormone deficiency. Hypothyroidism has also been reported in a minority of people. Cognitive ability varies; according to a literature review, the degree of impairment may fall anywhere between the mild and severe ends of the spectrum. Facial features of ring 18 include low-set, dysplastic ears, epicanthic folds, and hypertelorism. Micrognathia has also been reported. Genetic
Individuals with ring 18 have one of their two copies of chromosome 18 that has formed the shape of a ring. The ring is formed when the caps on  both the long arm (q) and the short arm (p) of one copy of chromosome 18 are lost and the new ends re-join to form the ring. Because the ring involves deletions of both the long arm (18q-) and the short arm (18p-) of chromosome 18, individuals with ring 18 can have features of both 18p- as well as distal 18q-.
Natural influenza infection is a stronger risk factor for the development of GBS than is influenza vaccination and the vaccination reduced the risk of GBS overall by lowering the risk of catching influenza.In the United States, GBS after seasonal influenza vaccination is listed on the federal governments vaccine injury table. On March 24, 2021, after reviewing several post-marketing observational studies, where an increased risk of Guillain–Barré syndrome was observed after 42 days following vaccination with the Zoster vaccine Shingrix, the FDA required safety label changes from the manufacturer GlaxoSmithKline to include warnings for risk of Guillain–Barré syndrome. COVID-19 infection or vaccine related
GBS has been reported in association with COVID-19, and may be a potential neurological complication of the disease. GBS has been reported as a very rare side effect of the Janssen and the Oxford–AstraZeneca COVID-19 vaccine for COVID-19 and European Medicines Agency (EMA) had issued warning to the patients and healthcare providers. The incidence of GBS following the vaccination with the Oxford-AstraZeneca vaccine was originally reported as being lower than the incidence of GBS following a COVID-19 infection. More recent studies, however, found no measurable link between COVID-19 infection and GBS, while correlations with a first dose of AstraZeneca or Janssen vaccines were still positive.COVID-19 has been reported as causing peripheral neuropathy and more recently some evidence of aggravation of autoimmune disorders including GBS. Some studies are now finding Parkinsons Disease is more common in infection survivors.