Differential Diagnosis

The patient's presentation is complex, with multiple laboratory abnormalities and a history of Hashimoto's thyroiditis. Here's a differential diagnosis organized into the requested categories:

• Single Most Likely Diagnosis
  • Hashimoto's Thyroiditis Flare: The presence of 870 TPO antibodies with normal thyroid function suggests a flare of the patient's known Hashimoto's thyroiditis. The slightly elevated monocytes could be indicative of chronic inflammation, which is consistent with autoimmune thyroiditis.
• Other Likely Diagnoses
  • Copper Deficiency: A blood copper level of 67 µg/dL is low, and copper deficiency can cause various symptoms, including fatigue, weakness, and immune system dysfunction. The patient's slightly low neutrophils could be related to copper deficiency, as copper is essential for neutrophil function.
  • Perimenopausal Symptoms: The hormone panel suggests perimenopause, which could be contributing to the patient's symptoms. Perimenopause can cause a range of symptoms, including fatigue, mood changes, and sleep disturbances.
• Do Not Miss Diagnoses
  • Hemochromatosis: Although the ferritin level is normal, hemochromatosis can cause copper deficiency, and the patient's low copper level warrants consideration of this diagnosis. Hemochromatosis can lead to serious complications, including liver damage and heart problems, if left untreated.
  • Infectious Disease: The slightly elevated monocytes and low neutrophils could be indicative of an underlying infection. Although the CRP is negative, it's essential to consider infectious diseases, such as endocarditis or osteomyelitis, which can have subtle presentations.
• Rare Diagnoses
  • Wilson's Disease: This rare genetic disorder causes copper accumulation in the body, but it can also cause copper deficiency in some cases. The patient's low copper level and history of Hashimoto's thyroiditis make this diagnosis worth considering, although it is unlikely.
  • Myelodysplastic Syndrome: The patient's slightly low neutrophils and elevated monocytes could be indicative of a myelodysplastic syndrome, a rare group of disorders that affect blood cell production. Although this diagnosis is unlikely, it's essential to consider it due to the potential for serious complications.