Challenges in HSV encephalitis: normocellular CSF, unremarkable CCT, and atypical MRI findings.

PURPOSE: Herpes simplex virus (HSV) encephalitis continues to be the most common form of sporadic lethal encephalitis worldwide. The wide spectrum of clinical presentations and laboratory findings often poses a diagnostic challenge for physicians which might delay administration of life-saving therapy with acyclovir. Atypical presentations of HSV encephalitis have become increasingly prevalent with better diagnostic techniques and have not been well studied. METHODS: We retrospectively evaluated all consecutive PCR-proven HSV encephalitis cases treated at the Hospital of the Ludwig-Maximilians-University in Munich, Germany from January 1, 2013 to February 28, 2018. RESULTS: We included 18 patients with PCR-proven HSV encephalitis. The most common clinical features were altered mental status (77.8%), focal neurologic deficits (72.2%) and fever (72.2%). Remarkably, four of these patients (22.2%) had a normocellular cerebrospinal fluid (CSF) on admission. Electroencephalography and magnetic resonance imaging abnormalities were highly sensitive for HSV encephalitis independent of CSF cell count. Striking atypical findings on MRI were extensive global brain swelling and severe brainstem involvement in single patients. Of note, initial CT scans were normal in 11 out of 16 patients (68.8%). All patients were treated with acyclovir. Three patients still developed a clinical deterioration under therapy with acyclovir with one patient requiring decompressive craniotomy due to bilateral space-occupying temporal lobe hemorrhage. 94.4% of the patients survived but only 38.9% were discharged with a good clinical outcome (Glasgow Outcome Score = 5). CONCLUSION: Atypical presentations of HSV encephalitis seem to be more common than previously thought and physicians should apply a high level of clinical suspicion and a low threshold to initiate life-saving acyclovir therapy in suspected cases.

Value of ultrasonography compared with physical examination for the detection of locoregional metastases in patients with cutaneous melanoma.

In several studies the early detection of locoregional metastases in patients with cutaneous melanomas has been shown to be of prognostic value. Physical examination alone often fails to detect locoregional metastases or cannot unambiguously classify palpable lymph nodes. This study aimed to evaluate the usefulness of high resolution ultrasonography for the early detection of locoregional metastases and to compare the sensitivity and specificity of ultrasound and physical examination. A prospective study was performed between January 1997 and June 1999 in 1395 patients (721 men and 674 women) with invasive cutaneous melanoma, treated and followed up at the Department of Dermatology and Allergology, Ludwig-Maximilian-University, Munich, Germany. A total of 2650 physical and ultrasound examinations of lymphatic drainage areas were performed, and lesions suspicious for metastases were excised and diagnosed by histopathology. The results of physical and ultrasound examinations were compared. Of the 2650 ultrasound examinations, metastases were suspected in 153, whereas 290 of the 2650 physical examinations were suspicious for metastatic disease. A total of 168 patients with suspicious lesions underwent surgery; histopathological examination revealed 112 melanoma metastases and 56 other diagnoses, including one second malignancy, one neurinoma, one haemangioma and 54 reactive lymph nodes. Ultrasonographic diagnosis of melanoma metastases had a sensitivity of 92.2% and a specificity of 98.2%, whereas diagnosis by physical examination had a sensitivity of only 51.3% and a specificity of 90.9%. Thus ultrasound examination was found to be highly effective and superior to physical examination for the early detection of locoregional melanoma metastases.