CJD is a reportable disease in Oklahoma; all clinical information from the index patient was obtained according to Oklahoma’s public health and safety code after confirmatory testing for fCJD was received in February 2012.⁸ Medical records were faxed to OSDH and reviewed by epidemiologists to collect pertinent symptom, laboratory, and exposure data. Additional family history was obtained from an interview with the index patient’s daughter. Notes were also reviewed from a 2003 fCJD investigation, which included interviews with the deceased patient’s sister, his neurologist, and 2 nieces. NPDPSC records were reviewed to confirm genetic testing results.

Confirmed fCJD cases included family members with brain autopsy test results consistent with the diagnosis of fCJD, verified after discussion with NPDPSC officials. Suspected cases included family members with progressive neurologic disease, ranging from persons with the diagnosis of Alzheimer’s disease to those described as having cognitive impairment, ataxia, and mutism, gathered from interviews with family members. A pedigree was constructed including all known confirmed or suspected fCJD cases using Microsoft Word 2010 software (Microsoft Corporation, Redmond, Washington).

The index patient was an African American man aged 56 years who initially presented to a hospital emergency department in August 2011 with mild tremors, dizziness, and memory disturbance. Results from an electroencephalogram (EEG) and brain magnetic resonance imaging (MRI) performed during hospital admission were indicative of encephalitis, and treatment with acyclovir and steroids was initiated. He was discharged home with a home health aide for assistance. During the next 2 months, he experienced worsening tremors, dysphagia, and speech impairment. He was readmitted to the hospital in October 2011 for dehydration and deconditioning. Results from a repeat EEG and brain MRI were consistent with CJD. He was discharged to home hospice and died in November 2011. Brain autopsy specimens were then sent to NPDPSC, where genetic testing demonstrated the D178N-129V mutation in the prion protein gene, consistent with the diagnosis of fCJD, in February 2012.

An interview with the patient’s daughter revealed she learned of a substantial family history of neurologic disease, including CJD, after conversing with distant family members at a different relative’s funeral in 2011. Prior to that, she was unaware that there was a family history of neurologic disease in a branch of her extended family. As the public health investigation progressed, OSDH epidemiologists realized that this case was potentially linked to a previously identified fCJD cluster among African Americans in Oklahoma involving at least 5 confirmed fCJD cases. During the 2003 investigation of a confirmed case of fCJD, genetic counseling had been recommended for 2 at-risk family members who both tested positive for the genetic mutation associated with fCJD. After reviewing notes from the prior epidemiologic investigations, including interviews with the 2003 case patient’s sister and 2 nieces, it was confirmed that both investigations involved the same pedigree.

In addition, a medical literature search for other fCJD clusters discovered a published report by Appleby et al⁴ describing 9 cases of confirmed or probable fCJD among a large African American family that resembled our pedigree. We contacted Dr Appleby and confirmed that our pedigree described the same family as the published pedigree.

Collectively, from the findings of prior OSDH public health investigations of CJD beginning in 2003, the 2012 investigation, the report by Appleby et al,⁴ and NPDPSC testing results, we identified a total of 8 confirmed cases (7 confirmed cases from NPDPSC, 1 confirmed case by brain biopsy performed at the University of Chicago) and 13 suspected cases spanning 7 generations in an African American family (Figure). As noted by Appleby et al,⁴ African Americans had not been previously described to carry fCJD mutations, but the first-generation male of this family was reportedly of mixed-race ancestry, which could have introduced the mutation into the family. Genetic counseling was recommended to the index patient’s daughter by OSDH.

Our investigation expanded a previously reported large fCJD pedigree among an African American family. With this report, we aim to raise awareness about fCJD and outline genetic testing options for CJD provided by NPDPSC. In addition, we emphasize the importance of confirming fCJD diagnoses in suspected cases, which is essential for informing persons of their potential hereditary risk. For persons in families affected by fCJD, genetic counseling can help facilitate informed decision making about genetic testing and family planning options that avoid the risk of passing the variant gene to future generations (ie, nonchildbearing, adoption, sperm or egg donation, in vitro fertilization with preimplantation genetic testing).^9,10

fCJD is unique because it is a hereditary disorder that is potentially transmissible iatrogenically by contaminated neurosurgical instruments or corneal or dura mater grafts, which is another important reason for individuals to be offered genetic counseling if family members have confirmed or suspected fCJD. Transmission through blood and solid organ donation is also possible. The American Red Cross excludes persons from donating blood who have received human pituitary growth hormone, a dura mater transplant, or those with blood relatives who had CJD because of concerns about secondary blood-borne transmission.¹¹ No formal CJD screening process exists for organ donation.

Public health officials and health care providers should continue to encourage brain autopsies for all suspected CJD patients to confirm diagnosis and classify CJD type. NPDPSC provides free autopsy services and facilitates access to pathologists who are willing to perform brain autopsies. Upon fCJD confirmation, the next step is to address questions and concerns of relatives through genetic counseling. This report illustrates that members within an affected family can remain unaware of their potentially devastating genetic history. Awareness among public health officials and health care providers about the availability of genetic counseling and other family planning options can empower those with a family history of CJD to learn more about their genetic predisposition and options available to prevent transmission.