Anti-Kelch-Like Protein 11 (KLH11), Serum

Anti-Kelch-like protein 11 (KLHL11) antibody encephalitis is a rare clinical condition characterized by autoimmune-mediated encephalomyelitis associated with the presence of KLHL11 antibodies. KLHL11 encephalitis is a distinct paraneoplastic syndrome frequently linked to testicular germ cell tumors, primarily seminoma. The rhombencephalitis phenotype commonly presents with ataxia, diplopia, dysarthria and vertigo. Hearing loss and tinnitus may precede other neurological symptoms by weeks to months. Some patients also exhibit clinical and MRI findings consistent with limbic encephalitis. Most individuals with this syndrome have inflammatory profiles in spinal fluid, particularly elevated oligoclonal bands. MRI of the brain often shows T2 fluid-attenuated inversion recovery (T2/FLAIR) abnormalities in the brainstem or limbic system. The associated neurological disorder is typically severe, though clinical improvement has been reported following cancer treatment or immunotherapy. This test works as an aid in evaluating patients with paraneoplastic or autoimmune encephalitis, such as brainstem encephalitis, limbic encephalitis or cerebellar ataxia, through serum testing.