case_images: PMC9878315_01
case_images: The gynecological ultrasound, pelvic CT, and cranial MRI results of the patient. (A) The gynecological ultrasound showed a mixed echogenic mass (8.3 cm x 5.9 cm) in the left ovary. (B) Pelvic CT showed an irregular cystic mass (10.2 cm x 8.4 cm) with a few calcifications and fatty components in the posterior aspect of the bladder. (C) Enhanced CT of the pelvis revealed a large cystic-solid mass in the anterior aspect of the uterus with no enhancement of the cystic component, fat and calcification, and mild enhancement of the solid component; A mass of uneven density on the right side of the uterus with a predominantly solid component, mild enhancement of the solid component and no enhancement of the fatty component. (D) The repeated gynecological ultrasound demonstrated no abnormal echogenicity. Initial cranial MRI exhibited an isolated splenium of the corpus callosum (SCC) lesion (arrows) with slight hypointensity on T1WI (E), hyperintensity on T2WI (F), FLAIR (G), and DWI (H), and hypointensity on the ADC map (I). On day 52 after onset, repeated MRI demonstrated the lesion of SCC lesion was completely resolved on T1WI (J), T2WI (K), FLAIR (L), DWI (M), and ADC (N).
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case_images: On the 17th day after initial symptoms, the abnormal signals of the SCC were characterized by slight hypo-intensity on T1-weighted image (T1WI), hyper-intensity on T2-weighted image (T2WI), FLAIR, and diffusion-weighted imaging (DWI) imaging, and hypo-intensity on apparent diffusion coefficient (ADC) map ( Figures 1E-I ). We further examined for tumor evidence and a gynecological ultrasound revealed a mixed echogenic mass in the left ovary ( Figure 1A ). Malignancy screening, including a CT of the chest, abdomen, and pelvis was performed to further assess the tumors, which demonstrated an irregular cystic mass (10.2 cm x 8.4 cm) with a few calcifications and fatty components in the posterior region of the bladder; ovarian teratoma was suspected ( Figure 1B ). A follow-up MRI scan ( Figures 1J-N ) indicated that the lesion in SCC had completely resolved 2 weeks after discharge. Enhanced CT of the pelvis revealed: a large cystic-solid mass (19 cm x 11 cm) in the anterior region of the uterus with no enhancement of the cystic component, fat and calcification, and mild enhancement of the solid component; A mass (3.3 cm x 2.9 cm) of uneven density on the right side of the uterus with a predominantly solid component, mild enhancement of the solid component and no enhancement of the fatty component ( Figure 1C ). The gynecological ultrasound demonstrated no abnormal echogenicity ( Figure 1D ).
case_images: Immunofluorescence staining of monkey cerebellar tissues. Cryosections of the monkey cerebellum were incubated with patient serum and CSF in the first step and with FITC-labeled goat anti-human IgG in the second step. Immunofluorescence of anti-NMDAR and anti-mGluR5 antibodies in the CSF and serum of the patient. Anti-mGluR5 and anti-NMDAR antibodies bound on mGluR5 and NMDAR antigens expressed in HEK293 cells, respectively, and visualized by the immunofluorescence of fluorescein on the second antibody. (A) Tissue-based indirect immunofluorescence assay of CSF displayed anti-NMDAR antibody presenting as granular fluorescence in monkey cerebellar granular layer cells. x200 magnification. (B) Positive reaction with transfected HEK293 cells expressing NMDAR after incubation with the patient's first CSF (B) (titer 1:3.2). x200 magnification. (C, I) Negative reaction with transfected HEK293 cells expressing mGluR5 after incubation with the patient's first CSF (C) and the repeated CSF (I). x200 magnification. (D, G, J, M) Tissue-based indirect immunofluorescence assay of the patient's first serum (D), second CSF (G), second serum (J), and third serum (M) showed no specific form of fluorescence in the monkey cerebellum. (E, K, N) Positive reaction with transfected HEK293 cells expressing NMDAR after incubation with the patient's first serum (titer 1:32) (E), second serum (titer 1:32) (K), and third serum (titer 1:10) (N). (F) Positive reaction with transfected HEK293 cells expressing mGluR5 after incubation with the patient's first serum (F) (titer 1:10). x200 magnification. (H) Negative reaction with transfected HEK293 cells expressing mGluR5 after incubation with the repeated CSF (H). x200 magnification. (L) Negative reaction with transfected HEK293 cells expressing mGluR5 after incubation with the repeated serum (L). x200 magnification.
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case_images: Considering the probability of AE, an antibody test of CSF using a cell-based assay combined with a tissue-based assay (EUROIMMUN Medical Diagnostics company) was also performed on the second day of admission ( Figures 2A-F ). Anti-mGluR5 antibody in the serum and anti-NMDAR antibody in the CSF were negative, respectively, and the titer of the anti-NMDAR antibody in the serum remained 1:32 ( Figures 2G-L ). At the 3-month follow-up, although her titer of anti-NMDAR antibodies in serum had decreased to 1:10 ( Figures 2M, N ), her daily life was not significantly affected and she resumed work.
case_images: The pathology results and surgical specimen of the patient. The specimen showed immature ovarian teratoma, consisting of neuroglia, primitive neural tube, infantile neural tissue, choroid plexus tissue, naive enamel organ, epidermis, hair follicle, and salivary gland tissue by H&E staining. The arrows indicate lesions in (B-H). (B) Neuroglia. (C) Primitive neural tube. (D) Infantile neural tissue. (E) Choroid plexus tissue. (F) Naive enamel organ. (G) Epidermis and hair follicle. (H) Salivary gland tissue. (A) The immature ovarian teratoma after surgical resection. The specimen showed mature ovarian teratoma, consisting of mature neuroglial, mature brain tissue, respiratory epithelium, mature adipose tissue, and keratocysts by H&E staining. The arrows indicate lesions in (K-N). (K) Mature neuroglial. (L) Mature brain tissue. (M) Respiratory epithelium. (N) Mature adipose tissue and keratocysts. (I, J) The mature ovarian teratoma after surgical resection.
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case_images: Intraoperatively, irregular tissue of the left adnexa was observed, with a size of approximately 27*21*7 cm ( Figure 3A ), and the right ovary was slightly enlarged; a papillary bulge was visible on the surface of the ovary, with a size of approximately 1*0.5*0.5 cm ( Figures 3I, J ). The pathology report showed: immature cystic teratoma (histological grade 2, clinical stage IC) in the left ovary, comprising neuroglia, primitive neural tube, Infantile neural tissue, choroid plexus tissue, naive enamel organ, epidermis, hair follicle and salivary gland tissue ( Figures 3B-H ); Mature cystic teratoma in the right ovary, consisting of mature neuroglial, mature brain tissue, respiratory epithelium, mature adipose tissue and keratocysts ( Figures 3K-N ).
case_images: Timeline with clinical manifestation, treatment progression, and diagnosis time.
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case_images: The entire course of the disease and the therapeutic modalities used have been summarized as a graphical abstract ( Figure 4 ).