Pertussis toxin "Bordetella" is that "B. pertussis" produces PT and the other species do not. "Bordetella parapertussis" shows the most similarity to "B. pertussis" and was therefore used for research determining the role of PT in causing the typical symptoms of whooping cough. Rat studies showed the development of paroxysmal coughing, a characteristic for whooping cough, occurred in rats infected with "B. pertussis". Rats infected with "B. parapertussis" or a PT-deficient mutant of "B. pertussis" did not show this symptom; neither of these two strains produced PT. A large group of bacterial exotoxins are referred to as "A/B toxins", in essence because
Unverricht–Lundborg disease ULD, MRIs taken once the disease has progressed show characteristic damage, which may help to correct a misdiagnosis. While ULD is a rare disease, the lack of well defined cases to study and the difficulty in confirming diagnosis provide strong evidence that this disease is likely under diagnosed. Unverricht–Lundborg disease is also known as EPM1, as it is a form of progressive myoclonic epilepsy (PME). Other progressive myoclonic epilepsies include myoclonus epilepsy and ragged red fibers (MERRF syndrome), Lafora disease (EPM2a or EMP2b), Neuronal ceroid lipofuscinosis (NCL) and sialidosis. Progressive myoclonic epilepsies generally constitute only a small percentage of epilepsy