A 74-year-old woman with a parathyroid tumor had an unusual combination of two rare diseases: primary hyperparathyroidism and Gitelman syndrome, a kidney disorder. According to Gram Research analysis, her dangerously low potassium (2.5 mmol/L) and magnesium (0.23 mmol/L) levels didn’t improve even after surgery removed the parathyroid tumor, revealing the hidden kidney disease. This case teaches doctors to suspect underlying kidney disorders when parathyroid patients don’t respond normally to treatment.
Doctors discovered something unusual in a 74-year-old patient: she had two rare conditions at the same time. She had primary hyperparathyroidism (a gland problem causing too much calcium in the blood) combined with Gitelman syndrome (a kidney disorder affecting mineral balance). What made this case special was that her symptoms didn’t match the typical pattern—she had dangerously low potassium and magnesium levels that wouldn’t improve with standard treatment. After surgery to remove the parathyroid gland, her calcium levels improved, but her magnesium stayed low, confirming the hidden kidney condition. This case teaches doctors to look for hidden diseases when patients don’t respond to normal treatment.
Key Statistics
A 2026 case report published in Frontiers in Endocrinology described a 74-year-old woman with primary hyperparathyroidism and concurrent Gitelman syndrome, presenting with severe hypercalcemia (4.18 mmol/L), hypokalemia (2.5 mmol/L), and severe hypomagnesemia (0.23 mmol/L) that persisted after parathyroid surgery.
The patient’s parathyroid hormone level reached 243.0 pg/mL with paradoxical hypocalciuria (calcium-to-creatinine ratio of 0.0093), an unusual pattern that prompted investigation for underlying renal tubulopathy.
Despite vitamin D supplementation and surgical removal of the parathyroid adenoma, the patient’s magnesium remained severely low, confirming the presence of a separate genetic kidney disorder (Gitelman syndrome).
The Quick Take
- What they studied: A single patient who had unusual mineral imbalances that didn’t fit the typical pattern of a parathyroid gland problem, suggesting a hidden second condition.
- Who participated: One 74-year-old woman who came to the hospital confused and dehydrated with dangerously imbalanced minerals in her blood.
- Key finding: The patient had two rare diseases at once: a parathyroid gland tumor and Gitelman syndrome (a kidney disorder). Even after removing the tumor, her magnesium stayed dangerously low, proving the kidney disease was real and separate.
- What it means for you: If you have a parathyroid problem that doesn’t improve with normal treatment, especially with low potassium or magnesium levels, doctors should check for hidden kidney disorders. This is rare but important to catch.
The Research Details
This is a case report—a detailed medical story about one patient. Doctors documented everything that happened: her symptoms when she arrived at the hospital, all her blood test results, imaging scans, surgery findings, and what happened afterward. They carefully tracked her mineral levels (calcium, potassium, magnesium, and phosphate) before and after treatment.
The doctors used several diagnostic tools: blood tests to measure minerals and hormones, urine tests to see what minerals her kidneys were losing, ultrasound and CT scans to find the tumor, and surgery with tissue examination to confirm the diagnosis. They also tested her vitamin D levels because that can affect how the body handles minerals.
This approach allowed them to piece together that the patient had two separate conditions happening at the same time, which is extremely rare and easy to miss.
Case reports are important because they describe unusual situations that doctors might not see often. By publishing this story, the doctors warn other physicians: ‘If you see this pattern, look for a hidden second disease.’ This helps other doctors make faster, better diagnoses in similar patients.
This is a single case, so it describes one person’s experience, not a pattern across many people. However, the doctors documented everything thoroughly with lab tests, imaging, and surgery confirmation. The key strength is that they solved the mystery—the patient’s symptoms improved after surgery for the first disease but didn’t fully resolve, which proved the second disease was real. Readers should understand this teaches a lesson but doesn’t prove the two diseases always occur together.
What the Results Show
The patient arrived at the hospital with severe confusion and dehydration. Blood tests showed dangerously high calcium (4.18 mmol/L, which is very high), low potassium (2.5 mmol/L), and severely low magnesium (0.23 mmol/L). Her parathyroid hormone was extremely elevated at 243.0 pg/mL, pointing to a parathyroid gland problem.
What was strange: her urine showed she was losing massive amounts of potassium and magnesium through her kidneys—the opposite of what should happen with a parathyroid problem. Even more puzzling, her urine calcium was surprisingly low (calcium-to-creatinine ratio of 0.0093), which shouldn’t happen when blood calcium is dangerously high.
Doctors gave her fluids and mineral replacements, but her potassium and magnesium stayed dangerously low. This resistance to treatment was the red flag that something else was wrong. Imaging found a tumor on her parathyroid gland, which was surgically removed.
After surgery, her blood calcium returned to normal, but her magnesium remained dangerously low despite vitamin D supplements. This proved she had a second, separate kidney disease (Gitelman syndrome) that was causing her body to waste magnesium.
The patient also had vitamin D deficiency (level of 14.2 ng/mL), which can worsen mineral imbalances. Her metabolic alkalosis (blood too alkaline) was connected to her low potassium. The urine tests showed a specific pattern of mineral wasting typical of Gitelman syndrome, a rare inherited kidney disorder where the kidneys can’t properly handle potassium and magnesium.
Primary hyperparathyroidism typically causes high calcium, low phosphate, and high urine calcium. Low potassium and magnesium are extremely rare in pure hyperparathyroidism. This case is unusual because it combines hyperparathyroidism with Gitelman syndrome, which has only been reported a handful of times in medical literature. The case highlights that when patients don’t fit the typical pattern, doctors should suspect multiple conditions.
This is one patient’s story, not a study of many people, so we can’t say how often this combination occurs. The case doesn’t prove that Gitelman syndrome causes hyperparathyroidism or vice versa—they may just happen to occur together by chance. We don’t know if this patient’s family members have similar conditions. The findings apply to this specific case and serve as a warning sign for doctors, not a definitive pattern.
The Bottom Line
If you have a parathyroid problem (hyperparathyroidism) that doesn’t respond normally to treatment, especially with persistent low potassium or magnesium, ask your doctor to check for hidden kidney disorders. Vitamin D supplementation alone may not fix mineral imbalances if a kidney disease is present. This is rare, but catching it early matters. Confidence level: This is based on one case, so it’s a cautionary lesson rather than proven treatment guidance.
This matters most for people with diagnosed hyperparathyroidism who aren’t improving as expected, and for doctors treating such patients. It’s also relevant for people with unexplained low potassium or magnesium levels. This doesn’t apply to people with normal parathyroid function or those responding well to standard hyperparathyroidism treatment.
In this case, the patient’s calcium improved within days after surgery, but the magnesium problem persisted for months, showing that some mineral imbalances take much longer to resolve if they’re caused by a separate kidney disease.
Frequently Asked Questions
Can you have two rare diseases at the same time?
Yes, though it’s uncommon. This case shows a patient with both hyperparathyroidism and Gitelman syndrome simultaneously. When symptoms don’t match typical patterns or don’t improve with standard treatment, doctors should test for multiple conditions occurring together.
What does it mean if my potassium and magnesium stay low after parathyroid surgery?
Persistent low potassium and magnesium after parathyroid treatment may indicate a separate kidney disorder like Gitelman syndrome. Ask your doctor to evaluate your kidney function and mineral-handling ability through specialized urine and blood tests.
How rare is Gitelman syndrome?
Gitelman syndrome is a rare inherited kidney disorder affecting about 1 in 40,000 people. Finding it combined with hyperparathyroidism is extremely unusual, with only a handful of cases reported in medical literature.
What symptoms should make me suspect a hidden kidney disease?
Muscle weakness, irregular heartbeat, confusion, or persistent low potassium and magnesium despite treatment warrant kidney evaluation. If you have hyperparathyroidism with these symptoms that don’t improve after surgery, ask your doctor about kidney tubulopathies.
Can vitamin D supplements fix low magnesium from Gitelman syndrome?
Vitamin D alone cannot fix magnesium loss caused by Gitelman syndrome. This kidney disorder requires specific treatment targeting the kidney’s mineral-handling defect. Standard supplementation may not be enough.
Want to Apply This Research?
- If you have hyperparathyroidism or are being treated for mineral imbalances, track your blood mineral levels (calcium, potassium, magnesium, phosphate) monthly. Record any symptoms like muscle weakness, confusion, or irregular heartbeat. Note whether these improve or persist after treatment.
- Work with your doctor to schedule regular blood tests to monitor all mineral levels, not just calcium. If symptoms don’t improve as expected, ask specifically about kidney function and whether you need additional testing for kidney disorders. Keep a symptom diary to share with your doctor.
- Set monthly reminders for blood work if you have a parathyroid condition. Track results in a spreadsheet or app to see if minerals are trending toward normal or staying abnormal. Share this data with your doctor to catch unexpected patterns early.
This case report describes one patient’s experience and is not medical advice. If you have been diagnosed with hyperparathyroidism or mineral imbalances, work closely with your endocrinologist or nephrologist. Do not change your treatment or supplementation based on this case alone. Persistent mineral imbalances after treatment require professional medical evaluation to rule out underlying conditions. This article is for educational purposes and should not replace consultation with qualified healthcare providers.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.