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What Do My MRI Scan Test Results Indicate?
Question: My father has been diagnosed with SIADH, and is on reduced fluids and salt tablets. An Mri did not come up positive for a tumour, but I have read that there can be tumour cells too small for an Mri to locate in the Pituitary gland, and that there is a blood test that would be better for diagnosis of tumour cells. So far there has been no cause identified for his condition. Last week he had a stroke of the left eye, which left him blind in that eye, and no symptoms of stroke elsewhere in his body. His blood thinner and blood pressure medications have both been increased. We have read of someone who had SIADH, and was diagnosed with sleep apnea, began using an apnea device, and his Sodium levels gradually became normal. Would my father be at an elevated risk for another stroke, and what further tests should they do to look for the cause of the Sodium imbalance? Also, could sleep apnea exhaust or stress the Pituitary gland, causing disruption of the secretion of other hormones, giving rise to SIADH? His apnea has not been officially diagnosed, but my Mom has been worried about it for decades, and tried to persuade him to go to a sleep clinic. He is not overweight, not a smoker, and not diabetic, nor does he have a known cardiac condition. He has dust and dander allergies and has been taking prednisone for many years previous. His vertebrae in the lower back have fractures and he manages the pain by walking a lot.
Brief Answer:
SIADH
Detailed Answer:
Sorry to learn about your father's bothersome symptoms.
1 What you have read about MRIs missing small tumors in the pituitary is true but uncommon.
Moreover this applies to a slightly different context. In SIADH, doctors are typically looking for larger tumors that disrupt the posterior part of the pituitary where the ADH cells are located. The ADH in SIADH stands for Anti Diuretic Hormone that is at the center of the problem.
So generally no further testing is necessary to locate a pituitary tumor. Now there are other brain and lung conditions including tumours that can lead to SIADH. Your doctor would have evaluated him for these I suppose.
2 Regarding your father's risk for another stroke, it would be best discussed with his neurologist based on a thorough assessment of his risk factors for this
3 Sleep apnea has been associated with lower testosterone levels in men owing to a lower pituitary signal of FSH and LH which are pituitary hormones. In many instancs, treatment of the sleep apnea rectifies the problem.
However, it has not been reported to work similarly in case of SIADH.
4 Considering your father has been on prednisone for a number of years, I would recommend testing for the possibility of adrenal insufficiency. An 8 am blood test for serum cortisol is a good start. It is very likely his doctors have already run this test and a thyroid check too. If not, these two are vitally relevant
5 With regards to his vertebral fractures, he needs a systematic work-up for osteoporosis such vitamin d and calcium blood tests, and a lateral spine Xray, and DXA bone density test with VFA (Vertebral Fracture Assessment)
6 When I see someone like him in my practice, I typically order the following blood tests in addition to a detailed physical examination:
CBC (Complete Blood Count, also known as Hemogram; includes Hemoglobin, WBC and Platelet counts)
Electrolytes (Sodium and Potassium in particular)
HbA1c (Glycosylated Hemoglobin = your last 3 months' glucose average). Also known by other names such as GlycoHemoglobin or Glycated Hemoglobin or A1c
Liver function tests (SGOT , SGPT, Albumin, Bilirubin, Alkaline Phosphatase)
Kidney function tests (BUN, Creatinine)
TSH (checks your thyroid)
Free T4 (this too checks your thyroid)
25 hydroxy Vitamin D levels (ideal range 40 to 60 ng/ml = 100 to 150 nmol/liter)
8 am serum Cortisol
Serum Osmolality by direct methid ('osmometer')
Urine osmolality
Urine Sodium
Uric acid
None of these tests require any fasting and can be done at any time of the day Correct diagnosis and treatment requires the opportunity to examine the patient so you must see an endocrinologist in-person.
SIADH
Detailed Answer:
Sorry to learn about your father's bothersome symptoms.
1 What you have read about MRIs missing small tumors in the pituitary is true but uncommon.
Moreover this applies to a slightly different context. In SIADH, doctors are typically looking for larger tumors that disrupt the posterior part of the pituitary where the ADH cells are located. The ADH in SIADH stands for Anti Diuretic Hormone that is at the center of the problem.
So generally no further testing is necessary to locate a pituitary tumor. Now there are other brain and lung conditions including tumours that can lead to SIADH. Your doctor would have evaluated him for these I suppose.
2 Regarding your father's risk for another stroke, it would be best discussed with his neurologist based on a thorough assessment of his risk factors for this
3 Sleep apnea has been associated with lower testosterone levels in men owing to a lower pituitary signal of FSH and LH which are pituitary hormones. In many instancs, treatment of the sleep apnea rectifies the problem.
However, it has not been reported to work similarly in case of SIADH.
4 Considering your father has been on prednisone for a number of years, I would recommend testing for the possibility of adrenal insufficiency. An 8 am blood test for serum cortisol is a good start. It is very likely his doctors have already run this test and a thyroid check too. If not, these two are vitally relevant
5 With regards to his vertebral fractures, he needs a systematic work-up for osteoporosis such vitamin d and calcium blood tests, and a lateral spine Xray, and DXA bone density test with VFA (Vertebral Fracture Assessment)
6 When I see someone like him in my practice, I typically order the following blood tests in addition to a detailed physical examination:
CBC (Complete Blood Count, also known as Hemogram; includes Hemoglobin, WBC and Platelet counts)
Electrolytes (Sodium and Potassium in particular)
HbA1c (Glycosylated Hemoglobin = your last 3 months' glucose average). Also known by other names such as GlycoHemoglobin or Glycated Hemoglobin or A1c
Liver function tests (SGOT , SGPT, Albumin, Bilirubin, Alkaline Phosphatase)
Kidney function tests (BUN, Creatinine)
TSH (checks your thyroid)
Free T4 (this too checks your thyroid)
25 hydroxy Vitamin D levels (ideal range 40 to 60 ng/ml = 100 to 150 nmol/liter)
8 am serum Cortisol
Serum Osmolality by direct methid ('osmometer')
Urine osmolality
Urine Sodium
Uric acid
None of these tests require any fasting and can be done at any time of the day Correct diagnosis and treatment requires the opportunity to examine the patient so you must see an endocrinologist in-person.
Note: For more information on hormonal imbalance symptoms or unmanaged diabetes with other comorbid conditions, get back to us & Consult with an Endocrinologist. Click here to book an appointment.
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Answered by
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