Ana Sanchez v. HHS - Tdap, chronic inflammatory demyelinating polyneuropathy (2022)

Ana Sanchez, a 31-year-old adult, received a Tdap vaccine on March 17, 2016. She alleged that this vaccine caused her to develop chronic inflammatory demyelinating polyneuropathy (CIDP).

Her symptoms, including numbness and weakness in her extremities, reportedly began around mid-April 2016, approximately 34 days after vaccination. The medical records showed varying diagnoses from treating physicians, with some suggesting Guillain-Barré syndrome (GBS) and others CIDP.

Petitioner's expert, Dr. Nahm, opined that the Tdap vaccine could cause CIDP through a cellular immune response mechanism and that Ms.

Sanchez's symptoms met the criteria for CIDP, with onset occurring within a medically acceptable timeframe. Respondent's expert, Dr.

Callaghan, argued that Ms. Sanchez likely suffered from GBS, with her ongoing symptoms attributable to pre-existing conditions rather than the vaccine.

He also contended that there was insufficient evidence to support a causal link between the Tdap vaccine and CIDP, and that the onset timeframe was too distant. The court found that Petitioner had not preponderantly established that the Tdap vaccine can cause CIDP, as the proposed causation theory lacked sufficient scientific reliability and was not adequately supported by the medical literature or case reports.

Furthermore, the court found that the evidence did not establish that the Tdap vaccine likely caused Ms. Sanchez's condition, noting pre-existing symptoms and other potential causal factors.

Although the onset timeframe was deemed medically acceptable, the claim was denied due to the failure to establish the first two prongs of the Althen test for off-Table claims.