CASES OF THE WEEK – “Primary Hyperparathyroidism Underdiagnosed among Kidney Stone Formers” by Dr ShekharShikare, Consultant & HOD, Nuclear Medicine

CASES OF THE WEEK – “Primary Hyperparathyroidism Underdiagnosed among Kidney Stone Formers” by Dr ShekharShikare, Consultant & HOD, Nuclear Medicine

Primary Hyperparathyroidism Underdiagnosed among Kidney Stone Formers (Short cases)

Increasing awareness of primary hyperparathyroidism screening may represent a key strategy for preventing recurrent kidney stones and other complications.

3% to 5% of patients with kidney stones have primary hyperparathyroidism (PHPT), which is a treatable cause of recurrent stones. However only 1 in 4 stone formers with hypercalcemia undergo testing for PHPT.

The apparent low prevalence of PTH testing in patient with kidney stones and hypercalcemia suggests low awareness among clinicians regarding this condition. We are missing an important opportunity to prevent recurrent kidney stones by diagnosing and treating PHPT. This is despite guidelines by the American Urological Association and European Association of Urology that recommend Calcium and PTH testing.

Case 1

Thirty-nine years old gentleman with past history of kidney stones four years ago which had passed after adequate hydration. At that time, he was found to have high calcium levels, but no further follow up was done. He did not report any renal episodes subsequently.

Recently he was admitted with hemoptysis and diagnosed as pneumonia ( covid negative). Found to have a mass behind the thyroid gland

CXR showed B/L interstitial infiltrates.

HRCT CHEST- Nearly complete consolidation of the left lobe. Mild pericardial effusion. Soft tissue mass measuring 26 x 15 x 25 mm located laterally to the upper thoracic trachea and posterior-inferiorly to the left lobe of thyroid gland? parathyroid nodule.

USG NECK- left infra thyroid paratracheal and esophageal loop related specific mass? atypical lymph node

FNAC of the nodule- Parathyroid tissue and possibly primary hyperparathyroidism (Adenoma).

Labs -Serum calcium 3.05 mmol/L (2.08- 2.65), PTH 18.50 pmol/L (1.95-8.49), TSH 1.14 (0.550-4.780 mIU/L), Vitamin D3 18.5 ng/ml, Sr creatinine 84 micromol /L (62-115), CRP 77

Referred for 99mTc-SESTAMIBI parathyroid scintigraphy

99mTc-SESTAMIBI PARATHYROID IMAGES

EARLY AND DELAYED MIBI IMAGES OF NECK AND CHEST

It shows focal area of increased MIBI tracer uptakes ( approximately  2.0*1.6*2.2  cms in size) seen inferio-posterior from the lower pole of left lobe of thyroid gland  on early images ( Better appreciated in SPECT-CT fused images) and persistent tracer retention is seen in the same of delayed washout images.

Thyroid gland shows comparatively decreased tracer uptakes on early images and adequate washout pattern on delayed images.

No focal area of any abnormal tracer uptakes seen in mediastinal region.

99mTc-THYROID IMAGES

The right lobe measures 4.4*2.0 cms in size and left lobe 5.2*2.4 cms in size approximately and good tracer uptakes. 

THERE IS FOCAL METABOLICALLY ACTIVE PARATHYROID ADENOMA

(approximately 2.0*1.6*2.2 cms in size) SEEN INFERIO-POSTERIOR FROM THE LOWER POLE OF THE LEFT LOBE OF THYROID GLAND ( figure 1,2 and 3)

Case 2

Forty-five years old gentleman with recent history of renal colicky pain on left side. On investigations found to have ureteric stone for which he underwent lithotripsy.  Besides this he also had a small stone in right kidney ( 2 mm).

Past history of left renal colic seven years back and found to have 14 mm stone, for which he underwent lithotripsy and became symptom free.

History of underlying diabetes mellitus, lipidemia, gout and on regular medications.

Investigations for recurrent renal calculi revealed high serum calcium and parathyroid hormone. Serum calcium 11.4 mg/dl (8.0-10.6), PTH 276.6 pg/ml (15.0-68.3), Serum creatinine 1.0 mg/dl (0.72- 1.18), Serum uric acid 6.4 mg/dl (3.5-7.2).

Referred for 99mTc-SESTAMIBI parathyroid scintigraphy

99mTc-MIBI PARATHYROID IMAGES

EARLY AND DELAYED MIBI IMAGES OF NECK AND CHEST

It shows focal area of increased MIBI tracer uptakes ( approximately  4.8 * 5.5 mm  in size) seen mid medial portion of right lobe posteriorly  on early images ( Better appreciated in SPECT-CT fused images) and persistent tracer retention is seen in the same region on delayed washout images (Better appreciated in SPECT-CT fused images

Thyroid gland shows asymmetrical tracer uptakes (right lobe relatively > than the left lobe) on early images and adequate washout pattern on delayed images.

No focal area of any abnormal tracer uptakes seen in mediastinal region.

THERE IS FOCAL METABOLICALLY ACTIVE PARATHYROID ADENOMA

(APPROXIMATELY 4.8 * 5.5 MM  IN SIZE) SEEN MID MEDIAL PORTION OF RIGHT LOBE POSTERIORLY (figure 1,2,3)

Case 3

Fifty-six years old lady with recent history of joint pain and palpitation since last two years and renal stones since last five to six years. 

Past history of hernia repair, cholecystectomy and hysterectomy.

On investigations found to have high serum calcium, parathyroid hormone and low Phosphorus.

Serum calcium 13.4 mg/dl (8.0-10.6), PTH 159.6 pg/ml (15.0-68.3), Serum Phosphorus inorganic 2.4 mg/dl (2.5- 4.5).

USG thyroid- MNG with possibility of right inferior parathyroid adenoma/cervical lymph node

Referred for 99mTc-SESTAMIBI parathyroid scintigraphy

99mTc-MIBI PARATHYROID IMAGES

EARLY AND DELAYED MIBI IMAGES OF NECK AND CHEST

It shows focal area of increased MIBI tracer uptake seen inferio-posterior portion ( approximately 10.2*2.8 mm in size) of the right lobe (Better appreciated in SPECT-CT fused images) and persistent tracer retention is seen in the same region on delayed washout images (Better appreciated in SPECT-CT fused images.)

Thyroid gland shows asymmetrical tracer uptakes ( right lobe relatively > than the left lobe) along with two areas of relatively increased MIBI tracer uptakes ( mid and lower portion of right lobe).

No focal area of any abnormal tracer uptakes seen in mediastinal region.

THERE IS FOCAL METABOLICALLY ACTIVE PARATHYROID ADENOMA

(approximately 10.2*2.8 mm in size) SEEN INFERIO-POSTERIOR PORTION OF THE RIGHT LOBE OF THYROID GLAND. 

Case 4

Twenty-nine years old gentleman with recent history of swelling in neck with little pain and flank pain on and off since last three weeks.

History of renal stones since last nine years (left kidney- urinary tract blocked due to renal stones, Right kidney- little sand present),

Past history of multiple surgeries for the renal stones (especially of the left kidney), recently stenting was done in left kidney and was removed one month ago.

On investigations found to have high serum calcium, parathyroid hormone and low Phosphorus.

Serum calcium 2.3 mmol/L (2.18-2.60), PTH 104.9 pg/ml (18.4-80.1), Serum free T4 16.42 pmol/L (11.5- 22.7), TSH 0.693 micro IU/ml (0.55-4.78)

USG thyroid- Goiter with colloidal cyst and nodules.

Referred for 99mTc-SESTAMIBI parathyroid scintigraphy

99mTc-MIBI PARATHYROID IMAGES

EARLY AND DELAYED MIBI IMAGES OF NECK AND CHEST

It shows focal area of increased MIBI tracer uptake seen inferio-posterior portion ( approximately 23.1* 14.3 mm in size) of the left lobe (Better appreciated in SPECT-CT fused images) and persistent mild tracer retention is seen in the same region on delayed washout images (Better appreciated in SPECT-CT fused images.)

Thyroid gland shows asymmetrical and relatively inhomogeneous tracer uptakes on initial images and on delayed washout images shows comparatively delayed washout out pattern.

No focal area of any abnormal tracer uptakes seen in mediastinal region.

THERE IS FOCAL METABOLICALLY ACTIVE PARATHYROID ADENOMA (approximately 23.1*14.3 mm in size) SEEN INFERIO-POSTERIOR PORTION OF THE LEFT LOBE OF THYROID GLAND. 

Discussion

Unlike most recurrent stone formers, those with PHPT have a good chance at permanent cure. This makes detection of PHPT a paramount aim for patients and their physicians. PHPT results in elevated  serum calcium and is detected by blood tests. The elevation of serum calcium can be slight and variable so patience and persistence matter a lot.

Once diagnosed, PHPT can be cured by surgery that modern instruments and techniques have made very safe and highly successful in the hands of expert parathyroid surgeons.

Primary Hyperparathyroidism Underdiagnosed Among Kidney Stone Formers.

Unique Cases 110a Unique Cases 110b Unique Cases 110c

There is focal metabolically active parathyroid adenoma

(approximately 2.0*1.6*2.2 cms in size) Seen inferio-posterior from the lower pole of the left lobe of thyroid gland ( figure 1,2 and 3)

Primary Hyperparathyroidism Underdiagnosed Among Kidney Stone Formers.

Unique Cases 111a Unique Cases 111b Unique Cases 111c

There is focal metabolically active parathyroid adenoma

(approximately  4.8 * 5.5 mm  in size) seen mid medial portion of right lobe posteriorly. (As shown in figure

1,2,3 as arrows)

Primary Hyperparathyroidism Underdiagnosed Among Kidney Stone Formers.

Unique Cases 112a Unique Cases 112b Unique Cases 112c

There is focal metabolically active parathyroid adenoma

(approximately 10.2*8.9MM  IN SIZE) SEEN INFERIO-POSTERIOR PORTION OF RIGHT LOBE OF THYROID GLAND (as shown in figure 1,2,3 as arrows)

Primary Hyperparathyroidism Underdiagnosed Among Kidney Stone Formers.

Unique Cases 113a Unique Cases 113b Unique Cases 113c

There is focal metabolically active parathyroid adenoma

(approximately 1 23.1*14.3 MM  IN SIZE) SEEN INFERIO-POSTERIOR PORTION OF LEFT LOBE OF THYROID GLAND (as shown in figure 1,2,3,4 as arrows)