A 15 kg child has a urine output of 360 mL during the past 12 hours. Calculate the child’s urine output in mL/kg/hour for this period of time. (Do not enter units).

Choice A reason:

Compartment syndrome is a condition where increased pressure within a muscle compartment leads to decreased blood flow, which can cause muscle and nerve damage. It is typically associated with severe trauma, fractures, or crush injuries. The symptoms include severe pain, swelling, and decreased sensation or movement in the affected limb. In this case, the child’s symptoms of redness, swelling, and tenderness following a spider bite, along with an elevated WBC, are more indicative of an infection rather than compartment syndrome.

Choice B Reason:

Osteomyelitis is an infection of the bone, which can occur following an injury or infection elsewhere in the body. The symptoms include redness, swelling, tenderness, and pain in the affected area, along with fever and elevated WBC. Given the child’s history of a spider bite and the presence of redness, swelling, tenderness, and elevated WBC, osteomyelitis is the most likely diagnosis. The unremarkable X-ray does not rule out osteomyelitis, as early stages of the infection may not show changes on X-ray.

Choice C Reason:

Osteogenesis imperfecta, also known as brittle bone disease, is a genetic disorder characterized by fragile bones that break easily. It is not associated with infections or elevated WBC. The symptoms of osteogenesis imperfecta include frequent fractures, blue sclerae, and hearing loss. The child’s symptoms of redness, swelling, and tenderness following a spider bite, along with an elevated WBC, are not consistent with osteogenesis imperfecta.

Choice D Reason:

Juvenile idiopathic arthritis (JIA) is a type of arthritis that occurs in children. It is characterized by persistent joint inflammation, pain, and swelling. While JIA can cause joint tenderness and swelling, it is not typically associated with a recent injury or infection, such as a spider bite. Additionally, JIA does not usually cause elevated WBC. The child’s symptoms are more indicative of an infection, making osteomyelitis the more likely diagnosis.

The correct answer is d) Central nervous system.

Choice A reason:

The musculoskeletal system is not primarily affected by abnormal phenylalanine levels. Phenylketonuria (PKU) is a metabolic disorder that primarily impacts the brain and cognitive functions. While muscle weakness can occur due to overall health deterioration, it is not the primary system affected by phenylalanine toxicity.

Choice B reason:

The renal system is not the main target of phenylalanine toxicity. Although the kidneys play a role in filtering blood and excreting waste, the toxic effects of phenylalanine accumulation are more pronounced in the brain. Therefore, the renal system is not the primary system affected by abnormal phenylalanine levels.

Choice C reason:

The GI system, or gastrointestinal system, is not the primary system affected by abnormal phenylalanine levels. While dietary management is crucial for individuals with PKU to control phenylalanine intake, the toxic effects are primarily seen in the brain. The GI system is involved in the absorption and digestion of nutrients, but it is not the main system impacted by phenylalanine toxicity.

Choice D reason:

The central nervous system (CNS) is the primary system affected by abnormal phenylalanine levels. Phenylketonuria (PKU) leads to the accumulation of phenylalanine in the brain, causing severe brain damage and cognitive impairments. High levels of phenylalanine can disrupt neurotransmitter synthesis and brain development, leading to intellectual disabilities and other neurological issues. Therefore, the CNS is the main system impacted by phenylalanine toxicity.