In Marcus v. Superior Court (1971) 18 Cal.App.3d 22, a patient who had sued for malpractice after undergoing an angiogram sought disclosure of the names of other of the doctor's patients who had undergone angiograms in the recent past. The court held that although disclosure of the fact that a person had consulted a doctor did not, in and of itself, violate the physician-patient privilege, disclosure of a list of patients who had undergone a particular test did violate the privilege by disclosing the nature of the treatment received, information from which the nature of the patient's ailment also was either disclosed or could be inferred.