Case Report

Paraneoplastic Syndrome Masquerading as Recurrent Cerebellar Vascular Injury: A Case Report

by Telisha Tausinga1, Mariam Asadian1, Meenu Singh2*

1University of Utah School of Medicine

2University of Utah Health Department of Internal Medicine

*Corresponding author: Meenu Singh, University of Utah Health Department of Internal Medicine

Received Date: 06 November, 2023

Accepted Date: 11 November, 2023

Published Date: 14 November, 2023

Citation: Tausinga T, Asadian M, Singh M (2023) Paraneoplastic Syndrome Masquerading as Recurrent Cerebellar Vascular Injury: A Case Report. Int J Cerebrovasc Dis Stroke 6: 167. DOI:


Stroke is second leading cause of death and disability worldwide. Thus, it is critical to perform prompt workups when patients present with the concerning signs and symptoms. However, many other medical conditions mimic stroke and can account for hospitalizations where stroke and vascular workups are pursued, oftentimes being costly not only to the patient but to the medical system. One category of under recognized mimics is paraneoplastic neurologic syndromes, which are a variety of neurologic disorders associated with systemic malignancy. Kelch-like protein 11 antibody is a recently discovered antibody associated with paraneoplastic neurologic syndromes. Herein, we present a unique case of a patient presenting with recurrent and persistent cerebellar stroke-like symptoms found to have an underlying Kelch-like protein 11 antibody-associated paraneoplastic syndrome. We review the entirety of his presentation, review the current literature on this paraneoplastic syndrome, and discuss implications from this case that can be applied in future practice.


Kelch-like protein 11 antibody-associated paraneoplastic syndrome (KLHL 11 PNS) is a novel autoimmune-driven process typically associated with malignancy. Approximately 90 patients with KLHL 11 PNS have been reported in the literature since the first case was described in 2019 [1,2]. These studies note that KLHL 11 PNS is most often characterized by brainstem and cerebellar involvement, both of which are common targets of paraneoplastic autoimmunity in this syndrome. Patients may present with gait instability, diplopia, and vertigo, with exam findings notable for dysmetria, nystagmus, nuclear or supranuclear gaze palsy, and dysarthria [1].

KLHL 11 PNS has a strong oncological association with testicular germ cell tumors (TGCT) seen in 78.7% cases, particularly seminoma seen in 54.1% cases. Cases involving small-cell lung cancer, lung adenocarcinoma, ovarian carcinoma, ovarian teratoma, laryngeal SCC and chronic lymphocytic leukemia have also been described [1,2]. Due to the rarity and novelty of KLHL 11 PNS, exact epidemiological data are still lacking, and its clinical spectrum is continually evolving. In this case report, we describe a unique presentation of KLHL 11 PNS in a patient with progressive stroke-like symptoms associated with underlying malignancy.

Case Presentation

A 69-year-old male with a past medical history of hypertension, pre-diabetes, coronary artery disease, and a recent diagnosis of prurigo nodularis several weeks prior, presented to the emergency department (ED) due to subacute onset of slurred speech, unsteady gait, dizziness, frequent falls, and unintentional weight loss of 28 kg over two months. Examination was remarkable for reduced vibration sense in bilateral lower extremities and extensive ulcerating rash on his neck and upper chest (Figure 1). Laboratory findings were significant for a low vitamin B12 level, microcytic anemia, hypokalemia, and hypomagnesemia (Table 1). B12 and electrolyte supplementation were provided without improvement. Magnetic resonance imaging (MRI) brain without contrast showed evidence of remote left superior cerebellar insult. (Figures 2,3). Inpatient admission was considered for further evaluation, however the patient strongly requested discharge. Thus, a plan was made for close patient follow-up with neurology and physical therapy.


Figure 1: Prurigo nodularis on initial presentation.


Reference Range


134 (L)

136 – 144 mmol/L


2.8 (L)

3.3 - 5.0 mmol/L


98 (L)

102 - 110 mmol/L

Carbon Dioxide


20 - 26 mmol/L

Blood Urea Nitrogen (BUN)


8 - 24 mg/dL


0.54 (L)

0.72 - 1.25 mg/dL



64 - 128 mg/dL



8.4 - 10.5 mg/dL


3.1 (L)

3.5 - 5.0 g/dL

White blood count (WBC)

11.32 (H)

4.30 - 11.30 k/uL


10.1 (L)

14.8 - 17.8 g/dL


32.7 (L)

44.2 - 53.0 %



159 - 439 k/uL

Mean corpuscular volume (MCV)

75.3 (L)

81.2 - 96.6 fL

Hemoglobin A1c

6.1 (H)

<=5.6 %


1.4 (L)

1.6 - 2.6 mg/dL

Erythrocyte sedimentation rate (ESR)

56 (H)

0 - 10 mm/hr

C-reactive protein (CRP)

12.6 (H)

0.0 - 0.8 mg/dL

Vitamin B1

60 (L)

70 - 180 nmol/L

Vitamin B6

13.2 (L)

20.0 - 125.0 nmol/L

Vitamin B12

177 (L)

180 - 914 pg/mL

Table 1: Obtained on initial presentation. All other labs were unremarkable including complete blood count (CBC) with differential, remainder of complete metabolic panel (CMP), urine toxicology and urinalysis.


Figure 2: MRI of the brain at presentation (A) demonstrates area of restricted diffusion in the left cerebellar hemisphere (yellow arrow). MRI of the brain one month later (B) demonstrates stippled new areas of restricted diffusion (red arrows) adjacent to the original lesion (yellow arrow).