The Case

A previously healthy 11-year-old girl presented for an urgent mental health consultation with her pediatrician due to parental concerns about weight loss, food restriction, and mood dysregulation. What is the diagnosis?

History

The urgent appointment was scheduled due to parental concern about the change in the patient’s food intake and lack of engagement with the family over the past few weeks. In the months prior, the patient had been experiencing bullying at school after being placed in a classroom with additional academic assistance. She stopped participating in soccer due to fatigue and missed her period the month prior. During the interview, she denied avoiding food to lose weight and said she was not interested in eating food due to a decrease in appetite. When questioned about the bullying, she did become tearful but denied anxiety, depression, and impulsivity. She admitted that sometimes she wants to die but that she has no intention and no plan. On review of systems, she reported waking up 1 to 2 times at night to urinate and using the bathroom every 2 hours at school. Her urination frequency was typical for her, and she said that she drinks a lot of water because she is thirsty. Vital signs taken indicated she had lost 10 lb since her last physical examination one year ago. Her body mass index was 16.8, blood pressure was 112/69 mm Hg, heart rate was 86 beats per minute (bpm), and temperature was 98.2 °F. Besides emotional distress during the interview, there was nothing remarkable about the patient’s physical appearance.

Differential diagnosis

The differential diagnosis in this case represents the primary care perspective in treating a child who presents with mental health changes. Although she is in the clinic due to symptoms that might represent a mental health condition, it is imperative that a primary care physician consider a broad differential that includes organic causes as well as a mental health diagnosis. As such, the treating physician quickly thought through the following Table.

Laboratory testing

Based on the initial conversation with the patient and her parents, in-office testing was performed to assess the physical effects of an eating disorder, considered the highest probability on the list of differential diagnoses. The physician also wanted to rule out physical causes for her behavior as well as weight loss. Blood and urine samples were collected in the clinic, and orthostatic hypotension blood pressure assessment was performed. The patient was positive for orthostatic hypotension, with a difference of 27 bpm between her supine heart rate and her heart rate 2 minutes after standing up. A positive orthostatic hypotensive blood pressure result reflects a reduction in her venous return as a result of her state of malnutrition.¹ An anorexia symptom blood panel was drawn. The centrifuged blood revealed a lipemic layer of serum, and the urinalysis dipstick showed large ketones (3+), 1000 mg/dL of glucose, and a specific gravity of 1.030. The patient was sent to the emergency department for diabetic ketoacidosis (DKA) due to the presence of glucose and ketones in her urine along with lipemic-appearing blood serum.

Hospital course

The patient was seen in the emergency department and was noted to be slightly pale but had an otherwise unremarkable physical examination. The emergency medicine physician ordered laboratory tests to screen for new-onset diabetes and for hypertriglyceridemia. The patient’s laboratory results were consistent with DKA and showed the patient’s blood glucose level to be 601 mg/dL, carbon dioxide level of less than 5 mmol/L, hyponatremia, and low potassium level. Endocrinology was consulted immediately, and laboratory tests were redrawn to ensure accuracy. The patient was admitted to the pediatric intensive care unit to be started on the DKA treatment protocol, which includes insulin infusion, intravenous fluids, and potassium replacement.² DKA resolved, and the patient’s electrolyte levels normalized. Once blood glucose level stabilized, the management and investigation of her high triglyceride and cholesterol levels were the primary focus.

The patient’s blood appeared lipemic, as previously seen with the blood drawn in the clinic. Her triglyceride level was greater than 10,000 mg/dL, and her total cholesterol was 1327 mg/dL. Gastroenterology was consulted, and the patient was started on atorvastatin, fenofibrate, enoxaparin prophylaxis, and a no-fat diabetic diet. An adolescent with a high triglyceride level greater than 1000 mg/dL often indicates a genetic variation that interferes with or inhibits triglyceride metabolism and significantly increases the risk for acute pancreatitis.³ An oral swab from the patient was sent out for genetic polymerase chain reaction (PCR) testing. Testing screened for 36 genes that may be pathogenic variants potentially explaining the patient's critically high triglyceride and cholesterol levels. The results of the genetic PCR testing did not identify any pathogenic variants. The patient did not develop pancreatitis, and her lipid values continued to show a downward trend during her hospital stay with daily repeat laboratory tests. An abdominal ultrasound was ordered due to palpation of an enlarged liver. The abdominal ultrasound results revealed an 18-cm liver and no other remarkable findings. The patient was discharged after 6 days of hospitalization and was instructed to follow up with endocrinology to manage diabetes and with cardiology for mixed hyperlipidemia. Although stable at discharge, lipid values were still remarkably elevated, with triglyceride level at 1884 mg/dL and total cholesterol at 892 mg/dL.

Follow-up

The cardiologist added eicosapentaenoic acid (EPA) fish oil to aid in lowering lipid values and continued the patient on a no-fat diet with fenofibrate and atorvastatin. After 2 months, a significant decrease in lipid values was seen, with total cholesterol at 146 mg/dL and triglyceride level at 79 mg/dL. Because of the normalization of the lipid values with the addition of EPA fish oil and fenofibrate, no further genetic testing was indicated. The decrease in the patient’s lipid values with the addition of EPA fish oil and fenofibrate supports a properly working lipoprotein lipase.^4,5 The patient was diagnosed with multifactorial chylomicronemia syndrome in the setting of type 1 diabetes. With the patient's diabetes well controlled, the cardiologist has allowed some fat to be introduced into her diet and will follow up with laboratory tests every 3 months. After hospital discharge, the patient began psychotherapy to discuss the initial presentation of mood dysregulation. The patient's mood improved significantly after managing the diabetes, and no psychiatric medication was initiated. The pediatrician continued to monitor the mental health of the patient beyond her diagnosis of DKA to ensure that any comorbid mental health conditions were identified and to ensure support for chronic illness.

Discussion

When evaluating a patient for psychiatric concerns, it is essential to recognize physical symptoms of nonmental illness. Comprehensive histories and prompt treatment can be a lifesaving intervention, such as in this case, because it is not uncommon for DKA to occur during the initial presentation of diabetes mellitus type 1.² The patient's initial presentation included nonspecific symptoms of DKA, such as weight loss, fatigue, and poor school performance, which could all be explained by an eating or mood disorder.² With further questioning by the behavioral pediatrician, diabetes mellitus was the most critical diagnosis to consider when discovering polydipsia and polyuria. After laboratory testing was completed and glucose and ketone values were known, DKA was the confirmed cause of weight loss, polydipsia, and polyuria.⁶ The severe mixed hyperlipidemia was due to uncontrolled diabetes mellitus type 1 and multifactorial chylomicronemia syndrome.

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References

1. Burns J, Shank C, Ganigara M, Saldanha N, Dhar A. Cardiac complications of malnutrition in adolescent patients: a narrative review of contemporary literature. Ann Pediatr Cardiol. 2021;14(4):501-506. doi:10.4103/apc.apc_258_20

2. El-Mohandes N, Yee G, Bhutta BS, Huecker MR. Pediatric diabetic ketoacidosis. In: StatPearls. StatPearls Publishing; 2025-. https://www.ncbi.nlm.nih.gov/books/NBK470282/

3. De La Torre A, Hamilton L, Wilson DP. Management of hospitalized children with severe hypertriglyceridemia. In: Feingold KR, Ahmed SF, Anawalt B, et al, eds. Endotext. MDText.com Inc; 2000-. https://www.ncbi.nlm.nih.gov/books/NBK553648/

4. Paquette M, Bernard S, Hegele RA, Baass A. Chylomicronemia: differences between familial chylomicronemia syndrome and multifactorial chylomicronemia. Atherosclerosis. 2019;283:137-142. doi:10.1016/j.atherosclerosis.2018.12.019

5. Backes J, Anzalone D, Hilleman D, Catini J. The clinical relevance of omega-3 fatty acids in the management of hypertriglyceridemia. Lipids Health Dis. 2016;15(1):118. doi:10.1186/s12944-016-0286-4

6. Toni G, Berioli MG, Cerquiglini L, et al. Eating disorders and disordered eating symptoms in adolescents with type 1 diabetes. Nutrients. 2017;9(8):906. doi:10.3390/nu9080906