A case of acute kidney injury caused by dapsone-induced methemoglobinemia in a patient with chronic kidney disease

Methemoglobinemia (MetHb), which is characterized by an increased methemoglobin level, is a rare but potentially fatal disorder caused by congenital enzyme deficiencies or exposure to oxidizing agents, including dapsone. Elevation in the methemoglobin level impairs the oxygen-carrying capacity of hemoglobin, produces functional anemia, and induces tissue hypoxia. Such hypoxia results in microcirculation injury and hypoperfusion in the tissue and organs, including the kidney, and is a risk factor for acute kidney injury (AKI). This paper reports a case of AKI caused by dapsone-induced MetHb in a patient with chronic kidney disease, in which the patient ingested approximately 1,500 mg of dapsone in a suicide attempt, which was treated with aggressive management, including methylene blue, ascorbic acid, and transfusion.

Measurement of Volume of a Swallow for Liquid Swallowing in Healthy Young Adults

PURPOSE: The aim of this study is to estimate one mouthful volume in a single swallow and average volume per swallow (AVS) in multiple swallows in the situation of toxic liquid poisoning. METHODS: Thirty five men and 35 women were included in this study. Each subject was asked to drink one swallow and three consecutive swallows from bottle containing water and a bottle containing saline separately. We calculated one mouthful volume in a single swallow and AVS in three swallows. One mouthful volume and AVS were compared according to sex and content, respectively. One mouthful volume of water and saline was then compared with AVS of each. RESULTS: Sixty seven adults(34 men; 26.9+/-3.2 years, 33 women; 25.6+/-2.4 years) completed the study. Men had larger one mouthful volume of water(49.1+/-19.9 ml vs 39.7+/-10.2 ml, p=0.02) and saline(20.7+/-10.9 ml vs 14.0+/-4.6 ml, p=0.004) and AVS of water(28.5+/-11.9 ml vs 21.5+/-5.9 ml, p=0.004) and saline(11.9+/-6.3 ml vs 7.9+/-2.0 ml, p=0.001) than women. One mouthful volume and AVS of saline swallow were lower than those of water swallow. AVS of three consecutive swallows was lower than one mouthful volume in water and saline swallow. CONCLUSION: We suggest that one mouthful volume in a single swallow is 21 ml in men and 14 ml in women and AVS in multiple swallows is 12 ml in men and 8 ml in women. AVS in multiple swallows is two-threefold lower than reference values(20~30 ml) commonly used in poisoning study.

The Clinical Impact of the Pneumonia Severity Index and the CURB-65 for Making Admission Decisions

PURPOSE: The aim of our study was to examine the discrepancies between the Pneumonia Severity Index (PSI) score, the CURB-65 [confusion, blood urea nitrogen, respiratory rate and blood pressure with age (65 years)] and the clinical judgment for making admission decisions, and we also wanted to evaluate the value of the PSI and CURB-65 as the indicators for detecting inappropriate hospitalization among the patients with low risk CAP. METHODS: The medical records of 286 patients who visited the emergency department with CAP were identified by their PSI and their CURB-65, and we reviewed whether there existed a clinical basis to justify their hospitalization. RESULTS: Of a total 286 patients, 225 patients were admitted to the hospital. Sixty five patients with a PSI of I or II, and 117 patients with a CURB-65 of 0 or 1 were admitted by clinical judgment. The factors that justified admission of a lower risk CAP group were medical conditions other than CAP (56.9% vs 70.1%; PSI vs CURB-65), failure of outpatient therapy (24.6% vs 19.6%), social needs (6.2% vs 2.6%) and hypoxemia in 1 patient (1.5% vs 0.9%, respectively). Of the patients in the low risk group according to the CURB-65, one five patient was hospitalized for suspicion of sepsis. The positive predicted values of the PSI and CURB- 65 for inappropriate hospitalization of low risk CAP patients were 10.8% and 5.9%, respectively. CONCLUSION: The PSI and CURB-65 had unacceptably low positive predictive values and this was due to the comorbid conditions that required in-hospital care for the patients with low risk CAP. These indices did not supersede clinical judgment for making the decision to hospitalize low risk patients with CAP.