Person:

Venna, Nagagopal

Retinal vasculopathy with cerebral leukodystrophy (RVCL) is a rare, autosomal dominant condition caused by mutations of the three-prime repair exonuclease-1 (TREX1). The phenotypic expressions range from isolated retinal involvement to varying degrees of retinopathy, cerebral infarction with calcium depositions, nephropathy, and hepatopathy. We report a case of RVCL caused by a novel TREX1 mutation. This patient’s multisystem presentation, retinal involvement interpreted as “retinal vasculitis”, and improvement of neuroimaging abnormalities with dexamethasone led to the accepted diagnosis of a rheumatologic disorder resembling Behçet’s disease. Clinicians should consider RVCL in any patient with retinal capillary obliterations associated with tumefactive brain lesions or nephropathy.

Objective: To describe a novel manifestation of lower motor neuron disease in patients with well-controlled HIV infection. Methods: A retrospective study was performed to identify HIV-positive individuals with acute, painful lower motor neuron diseases. Results: Six patients were identified with HIV and lower motor neuron disease. Two patients met the inclusion criteria of well-controlled, chronic HIV infection and an acute, painful, unilateral lower motor neuron paralytic syndrome affecting the distal portion of the upper limb. These patients had segmental T2-hyperintense lesions in the central gray matter of the cervical spinal cord on MRI. One patient stabilized and the second patient improved with immunomodulatory therapy. Conclusions: This newly described syndrome expands the clinical spectrum of lower motor neuron diseases in HIV.

Acute encephalitis, encephalopathy, and seizures are known rare neurologic sequelae of respiratory tract infection with seasonal influenza A and B virus, but the neurological complications of the pandemic 2009 swine influenza A (H1N1) virus, particularly in adults, are ill-defined. We document two young adults suffering from H1N1-associated acute respiratory distress syndrome and renal failure who developed cerebral edema. The patients acutely developed a transtentorial brain herniation syndrome including a unilateral third nerve palsy (dilated and unresponsive pupils), elevated intracranial pressure, coma, and radiological evidence of diffuse cerebral edema. In both patients, neurological deterioration occurred in the context of hyponatremia and a systemic inflammatory state. These patients illustrate that severe neurologic complications, including malignant cerebral edema, can occur in adults infected with H1N1 virus, and illustrate the need for close neurological monitoring of potential neurological morbidities in future pandemics.

The term small-fiber neuropathy (SFN) refers to the type of polyneuropathies that preferentially damage the small unmyelinated and thinly myelinated sensory or autonomic neurons [1]. Skin biopsy to determine the epidermal nerve-fiber density (ENFD) is the most de- finitive method in the diagnosis of SFN, but autonomic function testing can also be useful [2]. Importantly, electromyography and surface nerve-conduction studies (EMG/NCS) do not capture the small scattered action potentials of small fibers, and thus are insensitive to small-fiber restricted neuropathies. Quantitative sensory testing is a subjective test that depends on patient volition, so it is not recommend- ed or reimbursed for clinical use [3]. Most generalized polyneuropathies first affect the distal parts of the limbs, such as the feet. They only rarely present proximally and the diagnosis of a non-length dependent SFN is usually associated with symptoms beginning in the hands, face, or torso. Onset in the pelvic region is rare and the diagnosis can be missed. We report on two patients with an unexplained syndrome of somatic and visceral uro-genital sensory deficit with histologic evidence of SFN.