<prompt> Pseudomembranous colitis, all are true exceptToxin A is responsible for clinical manifestationToxin B is responsible for clinical manifestationBlood in stools is a common featureSummit lesions are early histopathological finding  <response>: Blood in stools is not commonly seen in pseudomembranous colitis. Two high molecular weight exotoxins A and B are involved in the pathogenesis of the condition. Reference: Textbook of Microbiology; Anathanarayan and panikers; 10th edition; Page no: 270 