Amino acid transport disorders are medical conditions associated with a failure of amino acids to be absorbed from the kidney or intestine. An example is Hartnup disease. Reference
External links

Milne MD (1971). "Disorders of intestinal amino-acid transport". J Clin Pathol. 5 (Suppl): 41–4. doi:10.1136/jcp.s3-5.1.41. PMC 1176258.
Medical use
Aciclovir is used for the treatment of herpes simplex virus (HSV) and varicella zoster virus infections, including:
Genital herpes simplex (treatment and prevention)
Neonatal herpes simplex
Herpes simplex labialis (cold sores)
Shingles
Acute chickenpox in immunocompromised patients
Herpes simplex encephalitis
Acute mucocutaneous HSV infections in immunocompromised patients
Herpes of the eye and herpes simplex blepharitis  (a chronic (long-term) form of herpes eye infection)
Prevention of herpes viruses in immunocompromised people (such as people undergoing cancer chemotherapy)Its effectiveness in treating Epstein–Barr virus (EBV) infections is less clear. It has not been found to be useful for infectious mononucleosis due to EBV. Valaciclovir and acyclovir act by inhibiting viral DNA replication, but as of 2016 there was little evidence that they are effective against Epstein–Barr virus, they are expensive, they risk causing resistance to antiviral agents, and (in 1% to 10% of cases) can cause unpleasant side effects.Aciclovir taken by mouth does not appear to decrease the risk of pain after shingles. In those with herpes of the eye, aciclovir may be more effective and safer than idoxuridine. It is not clear if aciclovir eye drops are more effective than brivudine eye drops.Intravenous aciclovir is effective to treat severe medical conditions caused by different species of the herpes virus family, including severe localized infections of herpes virus, severe genital herpes, chickenpox and herpesviral encephalitis. It is also effective in systemic or traumatic herpes infections, eczema herpeticum and herpesviral meningitis.