a 3-year - old male , known to have isolated speech delay , presented to the emergency department with severe body aches and inability to walk .
few days prior to his presentation , the child started to have flu - like symptoms in the form of rhinorrhea and low - grade fever .
this was followed by irritableness , hypoactivity , and inability to move his legs and arms .
he was seen in a private hospital where computed tomography of the brain and a lumber puncture were done that showed no abnormalities . in the next day , his condition continued to worsen .
he developed difficulty in swallowing and dark - colored urine , so he was transferred to our institution . upon physical examination ,
the laboratory tests showed elevated creatine kinase level ( 1 778 856 u / l ; normal range 20 - 200
u / l ) , elevated serum transaminases ( serum glutamic - pyruvic transaminase [ sgpt ] = 1857
u / l [ normal range 0 - 50 u / l ] , serum glutamic - oxaloacetic transaminase [ sgot ] = 8626 u / l [ normal range 0 - 50 u / l ] ) , and creatinine 0.72 mg / dl ( 0.3 - 0.7 mg / dl ) .
the child started on intravenous hydration and received 1 dose of intravenous immunoglobulin . on the second day ,
the creatine kinase and serum transaminase levels improved , with creatinine reaching 0.94 mg / dl , the highest level reached .
the creatine kinase and serum transaminase levels continued to improve gradually over the following days , with slow improvement in the clinical condition .
he received another 2 doses of intravenous immunoglobulin on days 13 and 14 of admission .
muscle biopsy showed endomysial inflammatory infiltrates , mostly composed of cd8 and cd4 lymphocytes ; myofibers necrosis mostly ventral portion of myofibers ; residual granular microcalcifications ; and terminal complement complex deposits that outline necrotic myofibers , all features compatible with necrotic myopathy and early rhabdomyolysis ( figure 2 ) .
the arrows showed the degenerated myofibers . upon discharge , the child had mild muscle aches , was able to sit , and move his arms and feet .
he had persistent weakness in the lower limbs , but was unable to walk , with a follow - up examination 1 month after discharge , revealing that the child was able to walk normally with positive deep tendon reflex .
two months after discharge , the creatine kinase level dropped to 193 iu / l .
rhabdomyolysis results from skeletal muscle breakdown due to various causes . viral myositis , trauma , and inherited disorders are the most common causes in the pediatric age group . 

the breakdown releases the normal cell contents into the bloodstream , including creatine kinase , myoglobin , phosphorus , and potassium .
rhabdomyolysis is suspected clinically when muscle aches , muscle weakness , and tea - colored urine are present .
the diagnosis is based on the high creatine kinase level , which is the most sensitive marker . although there is no established cutoff levels , a concentration 5 to 10 times higher than the upper limit of normal reference range ( ie , 500 - 1000
other laboratory indicators include serum and urine myoglobin concentrations that may be useful but not essential for the diagnosis . 
 
the most common complication of rhabdomyolysis is kidney damage . in recent large pediatric studies reported by mannix
et al and wu et al , it was shown that the rate of acute renal failure in the pediatric patients with rhabdomyolysis ranged from 5% to 8.7% .
the risk factors that predispose a patient with rhabdomyolysis for developing acute renal injury are creatine kinase level concentration more than 5000 u / l , creatine kinase value upon admission , and slower decline in the serum creatine kinase level .
other factors include high myoglobin level , persistent or abrupt increase in the potassium or calcium level , as well as persistent metabolic acidosis .
on the other hand , a recent study by fernandez et al showed that the most reliable predictor of acute renal failure and the need for dialysis is the creatinine level above 1.7 , despite the peak creatine kinase .
the mainstay for the prevention and treatment of acute kidney injury is early and aggressive volume resuscitation .
other management options include alkalization of the urine , forced diuresis with mannitol , and loop diuretics . in severe cases or
in our case , the child developed extremely high creatine kinase levels that were not reported in the literature .
a thorough literature review was done searching for high creatine kinase levels in patients with acute rhabdomyolysis . in 2014 , a case report described a pediatric patient with mcardle disease who developed rhabdomyolysis with a high 6-digit creatine kinase level reaching 500 000
2 pediatric cases were reported . in both , the creatine kinase levels reached were 60 000
a case report of an adolescent with rhabdomyolysis due to undiagnosed hypothyroidism was reported with a creatine kinase level that reached around 34 000
a research article in 2013 examined the clinical spectrum of patients with rhabdomyolysis presenting to the pediatric emergency department , in which the peak serum level of creatine kinase was 9825.1  23 079.1
the only risk factor for developing acute renal injury that our patient had was a high peak creatine kinase level upon admission . on the other hand ,
he did not develop metabolic acidosis and had a normal albumin and electrolytes levels throughout his hospitalization .
he responded very well to volume resuscitation with rapid decline in the creatine kinase level .
although he received intravenous immunoglobulin for the fear of guillain - barre syndrome or other underlying immune - mediated diseases , neither the creatine kinase level decline nor the clinical status improvement was affected by the intravenous immunoglobulin administration . the sharp decline in the creatine kinase level
there are no clues in the family history or the patient s personal history that may suggest an underlying inherited metabolic , muscular , or genetic disease .
, this could be the first presentation of lipin-1 mutation that causes recurrent rhabdomyolysis in children .
lipin-1 gene encodes the muscle - specific phosphatidic acid phosphatase , a key enzyme in triglyceride and membrane phospholipid biosynthesis .
the episodes of rhabdomyolysis are mostly triggered by intercurrent infections and fever and to a lesser extent by fasting or exercise .
the prognosis of lipin-1 deficiency is poor , with up to one - third of patients dying during an episode of rhabdomyolysis . in about 60% of patients with recurrent rhabdomyolysis ,
 rhabdomyolysis is an acute life - threatening condition that can occur in childhood secondary to many causes . 
 the authors report the case of a 3-year - old male child who presented with acute rhabdomyolysis . 
 the peak plasma creatine kinase level was extremely high . 
 the 2 main causes of rhabdomyolysis in childhood are viral myositis and trauma , which can sometimes lead to acute renal failure . the highest creatine kinase levels reported in the literature so far was a 6-digit level in 2014 case report . in this study , the authors report the case of a 7-digit creatine kinase level in a child secondary to viral myositis who did not require renal dialysis . 
Case Report
Discussion