In this study, total knee arthroplasty was performed in a patient with pigmented villonodular synovitis. During surgery, severe black discoloration of the articular cartilage and menisci was observed in the patient. According to literatures, this is the first case report of severe articular cartilage pigmentation in a patient with PVNS.

Hepatitis A virus (HAV) has some life-threatening extrahepatic complications, such as acute acalculous cholecystitis (AAC). We herein reported a HAV-induced AAC case in a young female, who developed acute liver failure (ALF) during the course of her disease and preform a literature review.

The patient is a 33-year-old Iranian woman without a significant past medical history with the full range of narcolepsy symptoms that started within two weeks after her recovery from COVID-19. Sleep studies revealed increased sleep latency and three sleep-onset rapid eye movement events, compatible with a narcolepsy-cataplexy diagnosis.

A 64-year-old man presented with asymmetric paresthesia and subsequent weakness of his feet and a 10-kg weight loss over 40 days. Electrodiagnostic studies revealed distal axonal sensory-motor polyneuropathy with ongoing axonal loss. A peroneal nerve biopsy showed intravascular proliferation of CD-20 positive lymphocytes, which suggested intravascular large B-cell lymphoma.

As far as we know, this is the 51st case of Hennekam Syndrome (HS) worldwide and the first one in an African American.1 Our patient met all diagnostic criteria for HS, type 2 (FAT4 mutation), as the disease onset was in adolescence.2,3

A 41-year-old female patient was referred to the head and neck surgery department because of a large midline submandibular mass that was diagnostic for functioning thyroid tissue in a totally ectopic location.

A 30-year-old man presented with sudden chest pain and evidence of multiple cystic lesions in both long and left-sided pneumothorax in HRCT. H&E stained section and IHC for CD1a and S100 were positive in lung samples. The patient was treated with the diagnosis of Isolated pulmonary langerhans cell histiocytosis.

Key Clinical Message: An elevated middle cerebral artery peak systolic velocity in the setting of non-diabetic hypertrophic cardiomyopathy may portend an especially poor prognosis.

Spinal intramedullary lipoma within the craniovertebral region is extremely rare. These lesions are often associated with spinal dysraphism. Here we present a non-dysraphic one. Our patient was a 56-year-old female who presented with progressive right shoulder pain and gait disturbance.

Papillary thyroid carcinoma of the pyramidal lobe is rare. We describe a case of a 77-year-old woman who corroborates current literature findings, namely greater presence of adverse prognostic factors. Upper Neck Papillary Thyroid Cancer is a new entity, proposed to group these tumors with potential clinical and therapeutic implications.

A 31-year-old man with fever, dyspnea, abdominal pain, and jaundice has been admitted to the hospital in the southeast of Iran. Due to the presence of a pathognomonic skin lesion (Tache noire), the patient was diagnosed with Mediterranean spotted fever (MSF) and was treated with doxycycline.

A 66-year-old breast ductal carcinoma patient developed obstructive jaundice, presenting with epigastric discomfort and dark-colored urine. Contrast-enhanced computed tomography and endoscopic retrograde cholangiopancreatography revealed bile duct stenosis. Brushing cytology and tissue biopsy confirmed bile duct metastasis, and a self-expandable metallic stent was placed/replaced endoscopically, extending the patient’s life.

It is difficult to anatomically understand the three-dimensional structure of the middle ear and temporal bone during surgery, and great surgical technique are required. Therefore, complications are avoided through simulation using a three-dimensional printer, which was effective in not only safe and reliable surgery but also educating young physicians.

A woman presented with intermittent left lower abdominal pain associated with a mass and didn't have any other symptoms. During the operation, a local inflammatory mass was found in left lower quarter of abdominal cavity. There are two bony foreign bodies in it. Postoperative pathology suggested an inflammatory mass.

Immunodeficient patients are less prone to develop serious complications of COVID-19 and cytokine storm. However, they are more likely to develop opportunistic infections that can mimic the symptoms of the SARS-CoV-2. we presented a 27-year-old male case of SARS-CoV-2, who was complicated with Pneumocystis jirovecii pneumonia, following treatment with rituximab.

Fibrodysplasia ossificans progressiva is a rare condition with an estimated prevalence of one in two million individuals. The condition is characterised by widespread heterotrophic ossification of skeletal muscles and ligaments. We report the case of an eight-year-old female patient and show the radiological progression of the condition.

A 7-year-old American short-haired cat was presented with blepharospasm in the right eye. The case was finally performed with orbital exenteration, leading to the diagnosis of feline restrictive orbital myofibroblastic sarcoma. Adjuvant chemotherapy with toceranib was given for one month after surgery. However, the case died four months after surgery.

Oral mucosal lesions may persist years before diagnosis of inflammatory bowel disease (IBD) and subsequent primary sclerosing cholangitis (PSC). It may be that a dental practitioner may be the first clinician to suspect IBD. Suspect IBD; early referral and close collaboration with a gastroenterologist are recommended.