The often overlooked digital tuft: clues to diagnosis and pathophysiology of neuropathic disease and spondyloarthropathy

OBJECTIVE: To assess diagnostic implications of abnormalities of the pedal digital tufts and to identify features to facilitate distinguishing of spondyloarthropathy and leprosy. BACKGROUND: Better criteria for distinguishing between these disorders are necessary if their character, natural history, and evolution are to be understood. METHODS: Pedal x rays of 91 consecutive patients with diabetes, 21 alcoholic patients, 100 with spondyloarthropathy, 8 with scleroderma, and 137 with leprosy, and 188 defleshed skeletons of individuals with alcoholism, syphilis, cerebrovascular disease, and paraplegia from the Terry and Hamman-Todd collections were examined for evidence of osseous and articular pathologies. Digital tuft abnormalities were divided into irregularity, divot, flattening, resorption, whittling, and fragmentation. RESULTS: Tuft divots were more common in alcoholics than in diabetic, and were more common in both than in the other groups studied. Tuft flattening was limited to alcoholic and neurosyphilis groups. Tuft whittling was especially prominent among individuals with spondyloarthropathy, contrasted with leprosy and diabetes. Aligned fractures were more common in diabetics than individuals with leprosy. Misaligned fractures were limited to individuals with leprosy and neurosyphilis. Leprosy and spondyloarthropathy were complicated by phalangeal and metatarsal whittling more commonly than other diseases studied. Background pedal abnormalities, derived from individuals with cardiovascular syphilis, cerebrovascular accidents, and paraplegia, was limited to abnormal divots only. CONCLUSIONS: Pedal digital tufts undergo a variety of pathological alterations useful in the recognition of disorders traditionally considered neuropathic in aetiology and in distinguishing differential considerations. Tuft flattening appears specific for alcoholism and neurosyphilis, and misaligned fractures seem specific for neurosyphilis and leprosy, providing differential assistance related to spondyloarthropathy. Conversely, periosteal reaction distinguishes spondyloarthropathy from leprosy.     

TNF-alpha inhibitors and congestive heart failure

Tumor necrosis factor-alpha inhibitors are among the new class of drugs that offer new options for psoriasis control. In addition to serving as a key mediator in psoriasis, elevated tumor necrosis factor-alpha levels have also been observed in patients with congestive heart failure, and clinical trials have been performed to examine the effects of tumor necrosis factor-alpha inhibitors, such as etanercept and infliximab, in such a population. Two large-scale trials examining the effects of etanercept in more than 2000 patients with heart failure did not indicate any increased risk of mortality or morbidity, and no US Food and Drug Administration warning has been issued regarding the use of etanercept in such a patient population. On the other hand, a study with infliximab showed significantly increased deaths, hospitalizations, and morbidity. Thus, infliximab>5 mg/kg is now contraindicated in patients with moderate-to-severe congestive heart failure (New York Heart Association functional class III/IV). If infliximab must be used, it should not exceed 5 mg/kg, and patients must be followed closely.     

Skin manifestations of mercury poisoning

Eight patients with skin lesions attributed to methylmercury exposure are reported. The outbreak of poisoning occurred in Iraq as a result of the handling and ingestion of treated grain find home-made bread. The skin manifestations were rather rare and varied in severity and histological appearance.     

Drug-induced iatrogenic intraparenchymal hemorrhage

Intracerebral hemorrhage is bleeding into the brain parenchyma with possible extension into the ventricles and subarachnoid space. Each year, approximately 37,000 to 52,400 people suffer from intraparenchymal hemorrhage (IPH) in the United States. This rate is expected to rise dramatically in the next few decades as a result of the increasing age of the population and a change in racial demographics. IPH accounts for 8% to 13% of all stroke cases and is associated with the highest mortality rate.     

Characterizing tourniquet induced hemodynamics during total knee arthroplasty using diffuse optical spectroscopy

Tourniquet use creates a reduced blood surgical field during total knee arthroplasty (TKA), however, prolonged ischemia may cause postoperative tourniquet complications. To understand the effects of tourniquet-induced ischemia, we performed a prospective observational study using quantitative broadband diffuse optical spectroscopy (DOS) to measure tissue hemodynamics and water and lipid concentrations before, during, and after tourniquet placement in subjects undergoing TKA. Data was collected for 6 months and, of the total subjects analyzed (n = 24), 22 were primary TKAs and 2 were revision TKA cases. We specifically investigated tourniquet-induced hemodynamics based upon subject-specific tissue composition and observed a significant relationship between the linear rate of deoxygenation after tourniquet inflation and water/lipid ratio (W/L, p < 0.0001) and baseline somatic tissue oxygen saturation, StO₂ (p = 0.05). Subjects with a low W/L ratio exhibited a lower tissue metabolic rate of oxygen consumption, (tMRO₂) (p = 0.008). Changes in deoxyhemoglobin [HbR] (p = 0.009) and lipid fraction (p = 0.001) were significantly different between high and low W/L subject groups during deoxygenation. No significant differences were observed for hemodynamics during reperfusion and total tourniquet time was neither significantly related to the hemodynamic hyperemic response (p = 0.73) nor the time to max StO₂ after tourniquet release (p = 0.57). In conclusion, we demonstrate that DOS is capable of real-time monitoring of tissue hemodynamics distal to the tourniquet during TKA, and that tissue composition should be considered. DOS may help surgeons stratify hemodynamics based upon tissue composition and eventually aid the preoperative risk assessment of vascular occlusions from tourniquet use during TKA.     

Expression of Fas ligand by microglia: possible role in glioma immune evasion

The immune-privileged status of the central nervous system is thought to limit the application of immunotherapy for treatment of malignant brain tumors. Because the Fas pathway has been proposed to play a role in immune evasion, we examined the effect of tumor environment on the expression of Fas ligand (FasL) in a mouse glioma model. Immunoblotting revealed the expression of membrane-bound FasL to nearly double when murine G26 gliomas were propagated intracranially (IC) as compared to subcutaneously (SC). Further analysis by flow cytometry revealed microglia, which were absent in the SC tumors, to account for half of the FasL expression in the IC tumors. Interestingly, when FasL activity was inhibited in IC tumors, the proportion of tumor-infiltrating leukocytes increased three-fold, reaching the same frequency as the SC tumors. These observations suggest that microglia are a major source of FasL expression in brain tumors and possibly contribute to the local immunosuppressive milieu of malignant gliomas.