Characteristics of pediatric rhabdomyolysis and the associated risk factors for acute kidney injury: a retrospective multicenter study in Korea

Background

The clinical features of pediatric rhabdomyolysis differ from those of the adults with rhabdomyolysis; however, multicenter studies are lacking. This study aimed to investigate the characteristics of pediatric rhabdomyolysis and reveal the risk factors for acute kidney injury (AKI) in such cases.

Methods

This retrospective study analyzed the medical records of children and adolescents diagnosed with rhabdomyolysis at 23 hospitals in South Korea between January 2007 and December 2016.

Results

Among 880 patients, those aged 3 to 5 years old composed the largest subgroup (19.4%), and all age subgroups were predominantly male. The incidence of AKI was 11.3%. Neurological disorders (53.6%) and infection (39.0%) were the most common underlying disorder and cause of rhabdomyolysis, respectively. The median age at diagnosis in the AKI subgroup was older than that in the non-AKI subgroup (12.2 years vs. 8.0 years). There were no significant differences in body mass index, myalgia, dark-colored urine, or the number of causal factors between the two AKI-status subgroups. The multivariate logistic regression model indicated that the following factors were independently associated with AKI: multiorgan failure, presence of an underlying disorder, strong positive urine occult blood, increased aspartate aminotransferase and uric acid levels, and reduced calcium levels.

Conclusions

Our study revealed characteristic clinical and laboratory features of rhabdomyolysis in a Korean pediatric population and highlighted the risk factors for AKI in these cases. Our findings will contribute to a greater understanding of pediatric rhabdomyolysis and may enable early intervention against rhabdomyolysis-induced AKI.

Screening for Fatal Traumatic Brain Injuries in Cerebrospinal Fluid Using Blood-Validated CK and CK-MB Immunoassays

A single, specific, sensitive biochemical biomarker that can reliably diagnose a traumatic brain injury (TBI) has not yet been found, but combining different biomarkers would be the most promising approach in clinical and postmortem settings. In addition, identifying new biomarkers and developing laboratory tests can be time-consuming and economically challenging. As such, it would be efficient to use established clinical diagnostic assays for postmortem biochemistry. In this study, postmortem cerebrospinal fluid samples from 45 lethal TBI cases and 47 controls were analyzed using commercially available blood-validated assays for creatine kinase (CK) activity and its heart-type isoenzyme (CK-MB). TBI cases with a survival time of up to two hours showed an increase in both CK and CK-MB with moderate (CK-MB: AUC = 0.788, p < 0.001) to high (CK: AUC = 0.811, p < 0.001) diagnostic accuracy. This reflected the excessive increase of the brain-type CK isoenzyme (CK-BB) following a TBI. The results provide evidence that CK immunoassays can be used as an adjunct quantitative test aid in diagnosing acute TBI-related fatalities.

Capture-induced exertional rhabdomyolysis in the Shortfin Mako Shark, Isurus oxyrinchus

BACKGROUND

Shortfin Mako sharks (Isurus oxyrinchus) are top-order predators in oceanic food chains. They are captured worldwide by commercial and recreational fisheries, but little is known about the effects that fishing has on the homeostasis and longevity of these animals.

OBJECTIVE

This study aimed to assess the health of Shortfin Mako sharks captured by recreational fishers off eastern Australia.

METHODS

Twenty-four sharks were captured, and their gender, length, weight, reproductive maturity, and stage were recorded. After blood and urine collection, serum analytes were quantified using standard biochemical methods, whereas urine was analyzed using semi-quantitative reagent strips, microscopic examination, centrifugation, and ammonium sulfate precipitation tests.

RESULTS

Six Makos presented with red-brown urine. The means of notable serum analytes were as follows: sodium 276 mmol/L, potassium 15.6 mmol/L, inorganic phosphate 10.6 mmol/L, magnesium 3.3 mmol/L, urea 325 mmol/L, creatinine 52 μmol/L, AST 2806 U/L, CK 240938 U/L, lactate 44.4 mmol/L, osmolarity 1160 mmol/L, and pH 7.13. These analytes differed from the respective sand tiger shark reference interval, which was used as a proxy for Makos. The red-brown urine was due to myoglobin and had a mean pH of 5.76 that, when combined with red-brown casts, led to a diagnosis of fishing-induced exertional rhabdomyolysis that occurred secondary to lactic acidosis, hypoxia, and hypovolemia. It was further exacerbated by hyperkalemia and acute renal failure, serious complications that often lead to mortality.

CONCLUSIONS

Practitioners caring for sharks and rays should consider collecting urine from free-living or aquarium animals when they are captured for examination and/or treatment, particularly at times with maximal seawater temperatures.

Craniopharyngioma presenting with severe hyponatremia, hyponatremia-induced myopathy, and panhypopituitarism: a case report

Background

Craniopharyngiomas are rare intracranial tumors commonly presenting with neurological symptoms. Reports of severe hyponatremia as a presenting manifestation of a craniopharyngioma and hyponatremia-induced myopathy are rare. We report the case of a patient with craniopharyngioma presenting with severe hyponatremia, panhypopituitarism, and hyponatremia-induced myopathy.

Case presentation

A 52-year-old Sri Lankan man presented with anorexia, nausea, fatigue, generalized muscle weakness, and cramps for 1 week. The onset of his illness had been preceded by vomiting and diarrhea for 1 day which he attributed to food poisoning. On examination, he had an apathetic disposition with a generalized “sallow complexion.” He was not dehydrated. Apart from reduced muscle power (4/5) and hyporeflexia, the neurological examination was normal. His serum sodium was 102 mmol/l; potassium 4.1 mmol/l; chloride 63 mmol/l; plasma osmolality 272 mosm/KgH₂O; urine osmolality 642 mosm/KgH₂O; and urine sodium 79 mmol/l. His creatine phosphokinase was 12,400 U/l, lactate dehydrogenase 628 U/l, aspartate aminotransferase 360 U/l, and alanine aminotransferase 64 U/l. His hormone profile revealed panhypopituitarism. An electromyogram showed nonspecific abnormalities while a muscle biopsy did not show any pathology. Magnetic resonance imaging of his brain demonstrated a well-defined craniopharyngioma with suprasellar extension. His pituitary gland was compressed and the pituitary stalk was displaced by the tumor. He had marked improvement in muscle power and rapid reduction of serum creatine phosphokinase levels paralleling the correction of severe hyponatremia, even before the initiation of hormone replacement.

Conclusions

This case illustrates the rare presentation of severe hyponatremia and hyponatremia-induced myopathy in patients with craniopharyngioma, awareness of which would facilitate early appropriate investigations and treatment.