Skin pigmentation associated with minocycline therapy

A patient on long-term minocycline therapy developed blue-black discoloration on the legs. Skin biopsy specimens from the pigmented areas were examined by light and electron microscopy and energy-dispersive X-ray microanalysis. Pigmented granules were present at all levels of the dermis and subcutaneous fat tissues. Ultrastructural examination showed electron-dense granular material within the cytoplasm of dermal macrophages and energy-dispersive X-ray microanalysis indicated that the granules contained iron. Thyroid tissue obtained by aspiration biopsy showed the presence of fine brown granules within the cytoplasm of the follicular epithelial cells. An extract of skin from the pigmented areas was subjected to high performance liquid chromatography and minocycline was detected.     

Evaluation of transcutaneous CO2 responses following acute changes in PaCO2 in healthy subjects

Background and objective: Transcutaneous blood gas‐monitoring systems with miniaturized SpO₂ (peripheral blood oxygen saturation)/PCO₂ combined sensors (TOSCATM) have been widely used. There are no reports of the inter‐ and intra‐individual variability in transcutaneous measurements of PaCO₂ (PtcCO₂) in response to acute progressive changes in PaCO₂. This study examined inter‐ and intra‐individual variability of PtcCO₂ measurements under semi‐steady‐state conditions, and characterized the behaviour of PtcCO₂ in response to acute progressive changes in PaCO₂. Methods: Subjects breathed mixed gases through a mouthpiece connected to an automatic arterial blood gas controller. Using end‐tidal PCO₂ and PO₂ as guides, PaCO₂ was controlled to increase and/or decrease between baseline and ≥ 60 mm Hg, in a stepwise (n = 9) or progressive fashion (n = 6). Arterial blood was sampled when needed. Results: Intra‐individual correlation coefficients between PtcCO₂ and PaCO₂ were excellent in all subjects (0.971–0.989); however, the slope of the regression line varied among subjects (1.040–1.335). Bias and limits of agreement (± 2 SD from bias) between PtcCO₂ and PaCO₂ were ?1.8 mm Hg and ?7.7 to 4.1 mm Hg. Changes in PtcCO₂ in response to acute progressive changes in PaCO₂ also varied among subjects. Conclusion: The PtcCO₂ measurement system allows reliable estimation of PaCO₂ in a given subject. However, caution is needed when comparing absolute values between subjects or when acute changes in PaCO₂ occur.     

A case of X-linked α-thalassemia/mental retardation syndrome: Analysis of hemoglobin by an automated glycated hemoglobin analyzer

A 5-year-old male patient with X-linked α-thalassemia/mental retardation syndrome is reported. He showed multiple minor anomalies including characteristic facial abnormalities, α-thalassemia, severe mental retardation, and hypogonadism. Analysis of his hemoglobin by high performance liquid chromatography using an automated glycated hemoglobin analyzer revealed an abnormal peak. Identification of an abnormal peak by an automated glycated hemoglobin analyzer will aid in the diagnosis of patients with X-linked α-thalassemia/mental retardation syndrome.     

Is This the Natural History of the Retention Wire? A Case Report

We report on a 71-year-old man who had a dual chamber pacemaker implanted in 1991. A Class IV fracture of the Telectronics Accufix 330–801 atrial lead was observed on a chest X ray in December 1993. Serial chest X ray and fluoroscopy documented stable position of the migrated fractured f wire. The patient remained asymptomatic and a decision for conservative monitoring was made. A subsequent finding of a right atrial mass on echocardiography and evidence of pulmonary embolism on lung scan prompted a change of strategy. The patient underwent atriotomy, and a right atrial thrombus was discovered associated with the fractured J retention wire, both of which were extracted uneventfully. This case is illustrative that despite apparent stability of a Class IV fracture, it may result in endothelial injury with a thrombogenic nidus and resultant complications.     

Fascicular Parasystole Associated with Tachycardia-Dependent Right Bundle Branch Block

A 43-year-old female with a chief complaint of palpitation was subjected to clinical electrophysiological studies. Initial standard 12-lead ECG revealed that her palpitation was caused by fascicular parasystole firing at the basic cycle length of 1.25-1.40 seconds, and that both sinus and parasystolic beats were associated with left anterior fascicular block and tachycardia-dependent RBBB. His-bundle electrocardiogram suggested that the parasystolic focus was located in the proximal portion of the anterior fascicle of the left bundle branch and that the site of tachycardia-dependent conduction block was located in the main right bundle branch. These findings suggest that diffuse pathological changes in the intraventricular conducting system were responsible for both the conduction block and automatic impulse formation in the present case.     

Clinical significance of serum hyaluronan in patients with chronic viral liver disease

In order to elucidate the clinical significance of serum hyaluronan in chronic viral hepatitis, serum hyaluronan concentrations were measured using a sandwich enzyme binding assay in 115 patients with chronic viral hepatitis. These findings were examined in relation to the results of laboratory liver tests, levels of serum markers for fibrosis and liver histological findings. Serum hyaluronan levels increased with the progress of liver disease, particularly in liver cirrhosis. There were no significant differences in serum hyaluronan levels among the cirrhotic patients according to Child's grade. Multivariate analysis showed that the significant independent predictors of serum hyaluronan were serum aspartate aminotransferase (P= 0.020), serum alanine aminotransferase (P= 0.008), serum cholinesterase (P< 0.001), particularly serum type IV collagen 7S domain (P< 0.0001), and the histological degree of liver fibrosis (P< 0.0001). These findings suggest that elevated serum hyaluronan levels are closely related to the severity of liver fibrosis. We assessed the predictive value of serum hyaluronan in differentiating cirrhosis from chronic hepatitis, constructing receiver operating curves; we found that serum hyaluronan was a better test for diagnosing cirrhosis than serum type IV collagen 7S domain and laboratory liver tests.     

When Pacemakers Fail: An Analysis of Clinical Presentation and Risk in 120 Patients with Failed Devices

Although pacemaker recalls are common, the optimal mechanism for risk assessment and triage of patients at risk for sudden loss of device system function is unknown. A retrospective chart review of 120 patients with factory proven failed devices was performed. Logistic regression analysis was used to determine clinical correlates of emergency room versus outpatient clinic presentation at time of device failure. Twenty-two patients (18%) presented to emergency and 98 (82%) to clinic. Sixty-three devices had no device output at the time of presentation. Multivariate logistic regression analysis revealed that antiarrhythmic drug use (odds ratio: 7.4, 95% CI: 2.0–28.0), atrioventricular nodal disease as an indication for pacing (odds ratio: 2.8, 95% CI: 1.2–3.0), and female gender (odds ratio: 2.2, 95% CI: 1.0–4.5) were the only significant correlates of emergency room presentations. Pacemaker dependency (escape heart rate < 40 beats/min) did not correlate with location of presentation even though no device output at the time of presentation was associated with emergency room presentation (odds ratio: 2.5, 95% CI: 1.1–5.8). Neither the presence of structural heart disease nor symptoms at the time of device implantation (syncope or presyncope) were correlated with location of presentation upon unexpected device failure. Although there were no deaths in the 120 failed devices studied, there were 26 deaths in the total group of 227 patients with recalled devices that could not be studied. Antiarrhythmic drug use, electrocardiographic pacing indication, and female gender may be more sensitive predictors of emergency room presentation and significant symptoms in the event of unanticipated pacemaker failure. The inability of any retrospective analysis to accurately assess mortality in the setting of pacemaker system failure underscores the need for prospective databases in recall situations.     

Influence of factors related to implant stability detected by wireless resonance frequency analysis device

Summary Resonance frequency analysis (RFA) was introduced as a method for measuring implant stability more than a decade ago. Implant stability quotient (ISQ) values obtained using a recently introduced wireless RFA device have made it possible to evaluate stability in a non‐invasive technique; however, there are few studies of the factors that affect ISQ values determined using this device. The aim of the present study was to evaluate the association between ISQ values determined by wireless RFA and various factors related to dental implant stability using a pig cortical bone model. Dental implants (Replace^® Select Tapered implants) with a length of 10 mm were placed into pig cortical bone samples, then, ISQ values were determined using wireless RFA under various conditions (probe orientation, diameter of implant, insertion torque and peri‐implant bone loss). The results of this study showed that ISQ values were not affected by the direction of the probe from parallel to perpendicular to the long axis of the pig bone or to the smart peg. In addition, the diameter of the implant did not have a significant effect on the measured ISQ values. Statistically significant correlations were found between insertion torque and ISQ values (Spearman’s test, P < 0·05), and lower ISQ values were observed for deeper peri‐implant vertical defects (Mann–Whitney U‐test, P < 0·05). A wireless RFA device appears to be useful for measuring implant stability within the limits of the present in vitro study.