Whipple's disease expert in the disease, applied novel diagnostic methods to stored tissue samples from Whipple's original patient, and demonstrated "T. whipplei" in these tissues. Whipple's disease Whipple's disease is a rare, systemic infectious disease caused by the bacterium "Tropheryma whipplei". First described by George Hoyt Whipple in 1907 and commonly considered a gastrointestinal disorder, Whipple's disease primarily causes malabsorption but may affect any part of the body including the heart, brain, joints, skin, lungs and the eyes. Weight loss, diarrhea, joint pain, and arthritis are common presenting symptoms, but the presentation can be highly variable and approximately 15% of patients do
Hartnup disease Hartnup disease Hartnup disease (also known as "pellagra-like dermatosis" and "Hartnup disorder") is an autosomal recessive metabolic disorder affecting the absorption of nonpolar amino acids (particularly tryptophan that can be, in turn, converted into serotonin, melatonin, and niacin). Niacin is a precursor to nicotinamide, a necessary component of NAD+. The causative gene, "SLC6A19", is located on chromosome 5. It is named after the English family, Hartnup, who suffered from this disease. Hartnup disease manifests during infancy with variable clinical presentation: failure to thrive, photosensitivity, intermittent ataxia, nystagmus, and tremor. Nicotinamide is necessary for neutral amino acid transporter production in the