Possible complications of genital herpes
HSV-1
Herpetic whitlow/gladiatorum* - Herpes on the finger/body; usually caused by HSV-1
Occular (eye) herpes* - Can resemble conjunctivitis (pink eye) and lead to blindness in some cases; usually caused by HSV-1
Herpetic encephalitis - Potentially fatal inflammation of the brain that is considered a medical emergency; usually caused by HSV-1; symptoms include confusion, seizures and drowsiness
Respiratory tract disease - In immunocompromised individuals, there is a risk of HSV-1 causing respiratory tract disease
Increased risk of Alzheimer's Disease - Some studies have linked HSV-1 (oral, but possibly genital as well) to Alzheimer's Disease
* Most likely to occur via autoinnoculation during a primary outbreak and before sufficient antibodies have been established (typically 3-4 months from exposure).
HSV-2
Aseptic meningitis - Inflammation of the brain lining that usually resolves on its own; more common during a primary outbreak and does not typically recur; symptoms include headache, neck stiffness and light sensitivity
Liver disease - In immunocompromised individuals, there is a risk of HSV-2 causing liver disease (herpetic hepatitis)
Increased risk of HIV - HSV-2 increases the risk of acquiring HIV by 2-3 times in *both* men and women, *regardless* of the presence of visible lesions or other symptoms and HSV antiviral meds (see above section)
Increased risk of cervical cancer - HSV-2 has been linked to an increased risk of cervical cancer, *if* co-infected with high-risk HPV
Both HSV-1 and HSV-2 can cause systemic disease and complications in immunocompromised individuals.
Potentially fatal neonatal infection (herpetic infection in newborns) can also be caused by both types, although HSV-2 is the more common and serious of the two. Fortunately, preventative measures can be taken during pregnancy and delivery.
Emis Moderator comment: all of these can be read about on patient.info for which I've included search result links below.
Patient leaflets - https://patient.info/search.asp?searchTerm=herpes&collections=Condition_Leaflets
PatientPlus articles aimed at GPs - https://patient.info/search.asp?searchTerm=herpes&collections=Prof_Ref
HSV-1 and Alzheimer's Disease - http://www.cbsnews.com/news/cold-sore-virus-linked-with-alzheimers-disease/
GH, HPV and cervical cancer risk - http://www.ncbi.nlm.nih.gov/pubmed/23080497