Nasal obstruction as a common side-effect of sildenafil citrate

Sildenafil citrate is an effective oral drug for erectile dysfunction. The main action of sildenafil is the enhancement of the effect of nitric oxide (NO) by inhibiting the cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase-5 (PDE-5), an enzyme responsible for degradation of cGMP. NO is also present in the nasal mucosa and is responsible for vasodilation causing congestion and nasal obstruction. The aim of this study was to detect the effect of sildenafil on nasal mucosa in terms of nasal obstruction. A total of 16 patients presented to urology clinic suffering from impotence and medicated with sildenafil were included in the study. Before and after oral administration of 50 mg sildenafil, in all of the patients the nasal patency was examined by active anterior rhinomanometry (a method of assessing nasal resistance) using air pressure of 150 Pascal. In addition, all patients were asked about their sensation of nasal patency to detect the symptomatic nasal obstruction. There was a significant decrease in nasal air flow values (cm(3)/s) (p < 0.05). Except for three cases, all patients indicated that they had the sensation of nasal obstruction after the use of sildenafil (p < 0.05). Nasal obstruction is a common complaint for the patients using Sildenafil.     

Somatic mutation of the CD95 gene in human B cells as a side-effect of the germinal center reaction

Somatic hypermutation specifically modifies rearranged immunoglobulin (Ig) genes in germinal center (GC) B cells. However, the bcl-6 gene can also acquire somatic mutations during the GC reaction, indicating that certain non-Ig genes can be targeted by the somatic hypermutation machinery. The CD95 gene, implicated in negative selection of B lymphocytes in GCs, is specifically expressed by GC B cells and was recently identified as a tumor suppressor gene being frequently mutated in (post) GC B cell lymphomas. In this study, the 5' region (5'R) and/or the last exon coding for the death domain (DD) of the CD95 gene were investigated in naive, GC, and memory B cells from seven healthy donors. About 15% of GC and memory, but not naive, B cells carried mutations within the 5'R (mutation frequency 2.5 x 10(-4) per basepair). Mutations within the DD were very rare but could be efficiently selected by inducing CD95-mediated apoptosis: in 22 apoptosis-resistant cells, 12 DD mutations were found. These results indicate that human B cells can acquire somatic mutations of the CD95 gene during the GC reaction, which potentially confers apoptosis resistance and may counteract negative selection through the CD95 pathway.     

Air Entrapment as a Cause of Transient Cardiac Pacemaker Malfunction

Air within a pacemaker pocket may cause transient malfunction of a replacement unipolar cardiac pacemaker. This was noted in a patient in whom entrapped air prevented tissue contact of the anode, resulting in complete cessation of myocardial stimulation and absence of an electrocardiographic pacemaker artifact. Methods for avoiding this complication are proposed.     

Rituximab as successful therapy in a patient with refractory paroxysmal cold hemoglobinuria

BACKGROUND: Paroxysmal cold hemoglobinuria (PCH) is a rare autoimmune hemolytic anemia (AIHA) attributed to a biphasic hemolysin known as the Donath-Landsteiner (DL) antibody. It is most commonly encountered as an acute transient AIHA after a viral infection in children; the disease resolves after cessation of the infection. The rarest form of PCH is a chronic form in adults that is not (nowadays) associated with infection and is not responsive to conventional therapies. Rituximab has been found to be effective therapy in other forms of AIHA, such as cold agglutinin syndrome, that are refractory to conventional therapies. We describe a case of PCH refractory to steroids that responded to rituximab therapy on two separate occasions. CASE REPORT: A 64-year-old woman with fatigue was found to be profoundly anemic with laboratory findings consistent with AIHA. She was admitted for the workup and management of her disease after she failed to respond to a course of oral steroids. Laboratory evaluation demonstrated a positive DL test suggesting PCH. She was given a course of rituximab that resulted in normalization of her hemoglobin concentration. She presented 9 months later with recurrent hemolysis. She was given another course of rituximab that again resulted in termination of hemolysis. The patient remained in remission since her last dose of rituximab 19 months previously. CONCLUSION: To our knowledge, this is the first report of an adult case of refractory PCH successfully treated with rituximab.     

Pulmonary hypertension in a patient with ARDS—a possible side-effect of dopamine treatment

A patient with severe acute pulmonary failure developed pulmonary hypertension with worsening of right ventricular failure during treatment with dopamine. Ventricular failure was demonstrated by changes in cardiac filling pressures, pulmonary vascular resistance and ventricular volumes. By changing from dopamine to isoproterenol infusion central hemodynamic parameters normalized within a few hours.     

Chronic paroxysmal hemicrania presenting as recurrent orbital inflammation

Patients with chronic headache associated with ocular symptoms regularly seek ophthalmologists' opinions. We report an unusual case of chronic paroxysmal hemicrania (CPH), a rare but well-described variant of cluster headache in a female presenting to an eye department with recurrent episodes of severe unilateral periorbital swelling with a chronic history of headaches. Clinical features, review of literature, and therapeutic response to indomethacin helped to establish the diagnosis as CPH. This is the first report of severe orbital inflammation with CPH to our knowledge.     

Transient paraplegia as a presenting feature of aortic dissection in a young man

This report describes a case of aortic dissection in a 32 year old man who presented with mild central chest pain and transient paraplegia. Complete recovery of paraplegia in aortic dissection has previously been reported but this is the first case report in which full resolution of the paraplegia occurred within half an hour of presentation. The case emphasises the importance of careful history taking and eliciting subtle clinical signs, which helped in arriving at the correct diagnosis in this unusual presentation.     

Thromboembolic events and haematological diseases: a case of stroke as clinical onset of a paroxysmal nocturnal haemoglobinuria

Some haematological diseases are associated to an increased risk of thromboembolic events. We report a case of paroxysmal nocturnal haemoglobinuria (PNH) in which a cerebrovascular event represented the first clinical manifestation of disease. PNH is associated to thromboembolic events, generally of venous districts often involving unusual locations such as mesenteric vessels, sagittal veins, inferior vena cava and renal veins.To our knowledge arterial thrombotic episodes are rare and the involvement of arterial cerebral vessels is exceptional. Then, our case points out the importance of investigating about haematological disorders in all patients presenting with a stroke, in which the common predisposing conditions are excluded.     

Influence of grapefruit juice on cisapride pharmacokinetics

OBJECTIVE: Grapefruit juice increases the oral bioavailability of several drugs metabolized by cytochrome P450 3A4. This study investigated the influence of grapefruit juice on the pharmacokinetics of oral cisapride, a substrate of CYP3A4. METHODS: Fourteen healthy volunteers received in random order 10 mg cisapride (Prepulsid) with 250 mL water or grapefruit juice after an overnight fast. Blood samples were taken for 25 hours and urine was collected for 36 hours after dosing. Plasma concentrations of cisapride and urinary norcisapride were measured by HPLC. The influence of grapefruit juice on pharmacokinetic parameters (mean +/- SD) was assessed with the Wilcoxon matched pairs test for 13 subjects (1 subject did not fast as instructed). RESULTS: Grapefruit juice increased cisapride maximum measured plasma concentration (Cmax; water, 65+/-398 ng/mL; grapefruit juice, 87+/-40 ng/mL; P = .009) and area under the plasma concentration-time curve from 0 to 25 hours [AUC(0-25); water, 418+/-280 h x ng/mL; grapefruit juice, 580+/-289 h x ng/mL; P = .005] and prolonged the time to reach Cmax (water, 1.26+/-0.36 hours; grapefruit juice, 1.72+/-0.55 hours; P = .02). Half-life was not affected. Urinary norcisapride recovery was similar and thus the partial apparent metabolic clearance to norcisapride was lower (P = .046) after grapefruit juice (89.5+/-41.2 mL/min) than after water (121.5+/-54.7 mL/min). There was considerable interindividual variation in the grapefruit juice effect [range of AUC(0-25) grapefruit juice/water ratio, 0.90 to 2.65). CONCLUSIONS: Grapefruit juice increases the oral bioavailability of cisapride, with large interindividual variation in the change in Cmax and AUC. Because cisapride has a wide therapeutic index, the interaction may not be of major clinical significance for efficacy, but further studies are necessary at steady state to rule out the possibility of side effects in susceptible individuals.     

Basilar Migraine Manifesting as Transient Global Amnesia in a 9-Year-Old Child

SYNOPSIS
A case of transient global amnesia in a nine year old child with a history of recurrent episodes of vertigoand a family history of migraine headache is described. The possibility that acute confusional state inchildren, presenting as transient global amnesia may represent a variant of basilar migraine is discussed.