A Case of Left-Sided Acute Appendicitis in a 45-Year-Old Man with Situs Inversus Totalis Managed by Emergent Laparoscopic Appendectomy

BACKGROUND Situs inversus totalis (SIT) is a rare congenital abnormality that includes mirror-image transposition of both the abdominal and the thoracic organs. It may remain undetected into adulthood until an acute medical emergency results in diagnostic imaging. This report presents a challenging case of left-sided acute appendicitis in a 45-year-old man with SIT. CASE REPORT A 45-year-old man with a medical history of gastroesophageal reflux disease, class 2 obesity, prediabetes, and elevated low-density lipoprotein cholesterol presented with severe acute abdominal pain localized in the left lower quadrant with localized tenderness, nausea, and 2 episodes of non-bloody and non-bilious emesis that started a day before the clinical encounter. Computed tomography of the abdomen and pelvis revealed previously undiagnosed congenital SIT. In addition, physical, laboratory, and radiological findings suggested early acute appendicitis with no evidence of complications. Hence, the patient was managed with an emergent laparoscopic appendectomy. Acute appendicitis was confirmed in the post-surgery histopathological examination. The post-surgery recovery was uneventful, and the patient was discharged home on the second postoperative day. CONCLUSIONS This report highlights that SIT may remain undiagnosed into adulthood and poses a challenge in the diagnosis of left-side appendicitis due to atypical symptom presentation, supporting the findings of previous case reports. Therefore, the inclusion of left-sided acute appendicitis in the differential diagnosis of abdominal pain in the left lower quadrant is warranted.

A Severely Dilated Gallbladder With Multiple Gallstones After Concomitant Laparoscopic Sleeve Gastrectomy and Childbirth in a Hispanic Woman

Independent studies have associated laparoscopic sleeve gastrectomy (LSG) and pregnancy with a higher incidence of gallstones, especially in Hispanic populations. However, the synergistic impact of these risk factors is currently unknown. We present the case of a 42-year-old Hispanic woman who initially identified intermittent upper right abdominal pain, which worsened over the last four days before the presentation. Abdominal ultrasound indicated hepatic steatosis, hepatomegaly, and cholelithiasis. A hydropic gallbladder with numerous gallstones, surrounding pericholecystic inflammatory changes, and mild intra-abdominal and pelvic ascites was confirmed by computed tomography. The patient underwent an uneventful robotic-assisted cholecystectomy. A gross examination of the gall bladder measuring 15.5 x 6 x 5.5 cm revealed multiple stones measuring 1.0-1.5 cm in the lumen, the largest of which was impacted in the neck. This case underscores the importance of considering ethnicity and pregnancy history while assessing the post-LSG risk of incident cholelithiasis.

Image-Quality Assessment of 3D Intracranial Vessel Wall MRI Using DANTE or DANTE-CAIPI for Blood Suppression and Imaging Acceleration

BACKGROUND AND PURPOSE

3D intracranial vessel wall MRI techniques are time consuming and prone to artifacts, especially flow artifacts. Our aim was to compare the image quality of accelerated and flow-suppressed 3D intracranial vessel wall MR imaging techniques relative to conventional acquisitions.

MATERIALS AND METHODS

Consecutive patients undergoing MR imaging had conventional postcontrast 3D T1-sampling perfection with application-optimized contrasts by using different flip angle evolution (SPACE) and either postcontrast delay alternating with nutation for tailored excitation (DANTE) flow-suppressed or DANTE-controlled aliasing in parallel imaging results in higher acceleration (CAIPI) flow-suppressed and accelerated T1-SPACE sequences performed. The sequences were evaluated using 4- or 5-point Likert scales for overall image quality, SNR, extent/severity of artifacts, motion, blood suppression, sharpness, and lesion assessment. Quantitative assessment of lumen and wall-to-lumen contrast ratios was performed.

RESULTS

Eighty-nine patients were included. T1-DANTE-SPACE had significantly better qualitative ratings relative to T1-SPACE for image quality, SNR, artifact impact, arterial and venous suppression, and lesion assessment (P < .001 for each, respectively), with the exception of motion (P = .16). T1-DANTE-CAIPI-SPACE had significantly better image quality, lesion assessment, arterial and venous blood suppression, less artifact impact, and less motion compared with T1-SPACE (P < .001 for each, respectively). The SNR was higher with T1-SPACE compared with T1-DANTE-CAIPI-SPACE (P < .001). T1-DANTE-CAIPI-SPACE showed significantly worse lumen (P = .005) and wall-to-lumen contrast ratios (P = .001) compared with T1-SPACE, without a significant difference between T1-SPACE and T1-DANTE-SPACE. T1-DANTE-CAIPI-SPACE scan time was 5:11 minutes compared with 8:08 and 8:41 minutes for conventional T1-SPACE and T1-DANTE-SPACE, respectively.

CONCLUSIONS

Accelerated postcontrast T1-DANTE-CAIPI-SPACE had fewer image artifacts, less motion, improved blood suppression, and a shorter scan time, but lower qualitative and quantitative SNR ratings relative to conventional T1-SPACE intracranial vessel wall MR imaging. Postcontrast T1-DANTE-SPACE had superior SNR, blood suppression, higher image quality, and fewer image artifacts, but slightly longer scan times relative to T1-SPACE.

Development of a Sensitive Diagnostic Assay for Parkinson Disease Quantifying α-Synuclein-Containing Extracellular Vesicles

OBJECTIVE

To develop a reliable and fast assay to quantify the α-synuclein (α-syn)-containing extracellular vesicles (EVs) in CSF and to assess their diagnostic potential for Parkinson disease (PD).

METHODS

A cross-sectional, multicenter study was designed, including 170 patients with PD and 131 healthy controls (HCs) with a similar distribution of age and sex recruited from existing center studies at the University of Washington and Oregon Health and Science University. CSF EVs carrying α-syn or aggregated α-syn were quantified using antibodies against total or aggregated α-syn, respectively, and highly specific, sensitive, and rapid assays based on the novel Apogee nanoscale flow cytometry technology.

RESULTS

No significant differences in the number and size distribution of total EVs between patients with PD and HCs in CSF were observed. When examining the total α-syn-positive and aggregated α-syn-positive EV subpopulations, the proportions of both among all detected CSF EVs were significantly lower in patients with PD compared to HCs (p < 0.0001). While each EV subpopulation showed better diagnostic sensitivity and specificity than total CSF α-syn measured directly with an immunoassay, a combination of the 2 EV subpopulations demonstrated a diagnostic accuracy that attained clinical relevance (area under curve 0.819, sensitivity 80%, specificity 71%).

CONCLUSION

Using newly established, sensitive nanoscale flow cytometry assays, we have demonstrated that total α-syn-positive and aggregated α-syn-positive EVs in CSF may serve as a helpful tool in PD diagnosis.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that total and aggregated α-syn-positive EVs in CSF identify patients with PD.

Erythrocytic α-synuclein contained in microvesicles regulates astrocytic glutamate homeostasis: a new perspective on Parkinson's disease pathogenesis

Parkinson's disease is a neurodegenerative disorder characterized by the transmission and accumulation of toxic species of α-synuclein (α-syn). Extracellular vesicles (EVs) are believed to play a vital role in the spread of toxic α-syn species. Recently, peripheral α-syn pathology has been investigated, but little attention has been devoted to erythrocytes, which contain abundant α-syn. In this study, we first demonstrated that erythrocyte-derived EVs isolated from Parkinson's disease patients carried elevated levels of oligomeric α-syn, compared to those from healthy controls. Moreover, human erythrocyte-derived EVs, when injected into peripheral blood in a mouse model of Parkinson's disease, were found to readily cross the blood-brain barrier (BBB). These EVs accumulated in astrocyte endfeet, a component of the BBB, where they impaired glutamate uptake, likely via interaction between excitatory amino acid transporter 2 (EAAT2) and oligomeric α-syn. These data suggest that erythrocyte-derived EVs and the oligomeric α-syn carried in them may play critical roles in the progression or even initiation of Parkinson's disease. Additionally, the mechanisms involved are attributable at least in part to dysfunction of astrocytes induced by these EVs. These observations provide new insight into the understanding of the mechanisms involved in Parkinson's disease.