introduction

Takayasu’s arteritis (TA) is an idiopathic, granulomatous, large vessel arteritis that primarily involves the aorta and its major arterial branches.1 It can cause a wide variety of clinical manifestations depending on the vessels involved. When the renal arteries are affected, patients may have renal failure or renovascular hypertension.2 Here we present a case of Takayasu’s arteritis that caused bilateral renal artery stenosis. This bilateral renal artery stenosis caused the patient to present with malignant hypertension. The clinical picture was further complicated by thrombotic microangiopathy secondary to malignant hypertension.

Case

A 20-year-old woman presents with right arm pain that increases with movement. His physical examination revealed weak pulses in the right radial artery and the right brachial artery. Her complete blood count was normal, creatinine was 0.8 mg/dl, but erythrocyte sedimentation rate was 50 mm/hour and C-reactive protein was 35 mg/l. MRI angiography revealed total occlusion of a 15 cm segment extending from the distal part of the subclavian artery to the right axillary artery and the proximal part of the right brachial artery, and collaterals extending to the distal part of the right brachial artery. The presence of these results with the other test results ruled out other pathologies that figured in the differential diagnosis and a diagnosis of Takayasu’s arteritis was established. She was treated with prednisolone, azathioprine and acetylsalicylic acid. During follow-up, pancytopenia occurred, which quickly normalized on discontinuation of azathioprine. After stopping azathioprine, she was treated with methotrexate which did not cause any cytopenia.

Three years later, a patient presented to our service with high blood pressure. Blood pressure was 170/110 mm Hg in the left arm and 130/100 mm Hg in the right arm. Funduscopic examination revealed grade 1 bilateral hypertensive retinopathy. His creatinine was 1.1 mg/dl and C-reactive protein was 30 mg/l. Abdominal CT angiography demonstrated reduced calibration of the aorta and increased wall thickness at the level of the renal arteries, near total occlusion of the lumen of the 1.5 cm proximal segment of the renal artery left from the level of the ostium (Figure 1) and an almost total occlusion of the lumen of the 3 cm proximal segment of the right renal artery from the level of the ostium (Figure 2). She received 32 mg of methylprednisolone (with a taper regimen). The methotrexate was stopped and she received the first dose of tocilizumab IV (at a dose of 8 mg/kg/month). She was given nebivolol, amlodipine and doxazosin as antihypertensive drugs and was discharged from hospital.

Figure 1 Almost total occlusion of the lumen of the 1.5 cm proximal segment of the left renal artery, from the level of the ostium.

Figure 2 Almost total occlusion of the lumen of the 3 cm proximal segment of the right renal artery, from the level of the ostium.

A month after her discharge, she presented to the emergency room with blurred vision in her left eye. Blood pressure was 190/100 in the left arm and 150/90 in the right arm. Fundus examination revealed bilateral grade 3 hypertensive retinopathy and serous retinal detachment in the left eye. Laboratory results revealed normal C-reactive protein, elevated creatinine (1.4 mg/dl), elevated lactate dehydrogenase (706 U/l), thrombocytopenia (88,000/mm3), low hemoglobin (9.82 g/dl) and low haptoglobin (

Due to the presence of overt bilateral renal artery stenosis secondary to Takayasu’s arteritis, no additional workup for secondary hypertension (such as aldosterone levels and plasma renin activity) is not possible. ‘has been done. In order to adequately control disease activity, a second dose of tocilizumab IV was administered and the dose of methylprednisolone was maintained at a dose of 20 mg/day. Tocilizumab was not switched to another biologic because this was only the second dose of tocilizumab and disease progression that caused bilateral renal artery stenosis had occurred on treatment with methotrexate. The dose of antihypertensives was increased and new antihypertensives were initiated. Despite treatment with maximum doses of carvedilol, doxazosin, amlodipine, IV furosemide, isosorbide mononitrate, and moxonidine, her blood pressure was not adequately controlled. His creatinine increased to 1.8 mg/dl and hypervolemia developed. His hemoglobin decreased to 7.65 g/dl and platelet count to 58,000/mm3. In order to break the vicious cycle of malignant hypertension, an intervention to treat renal artery stenosis was planned. Until the operation, she had undergone 7 ultrafiltration sessions in 10 days in our hemodialysis department. This modality had effectively removed excess fluid from the patient, causing her weight to drop from 87 to 77 kg. The interventional radiology department considered the right renal artery unsuitable for intervention. A balloon dilation was performed in the left renal artery and a stent was placed there. Figure 3 shows the conventional angiography image of the left renal artery after balloon dilation. After surgery, her blood pressure was under control with carvedilol, amlodipine and 4 mg/day doxazosin. Creatinine dropped to 0.7 mg/dl, platelet count increased to 173,000/mm3 and hemoglobin increased to 8.81 g/dl. She got out of the hospital.

picture 3 Conventional angiography image of the left renal artery after balloon dilation.

Two years after discharge, the patient is normotensive on carvedilol, amlodipine and low-dose doxazosin. His blood count, CRP, creatinine and LDH levels are normal. She continues to receive tocilizumab (which was converted to subcutaneous form after the COVID-19 pandemic), methylprednisolone 4 mg/day, and acetylsalicylic acid.

Discussion

Malignant hypertension is the most severe presentation of hypertension. The original definition includes the coexistence of very high blood pressure and signs of advanced stages of hypertensive retinopathy at the time of diagnosis. New definitions emphasize the presence of damage to organs such as the eyes, kidneys and heart, as well as an uncontrolled rise in blood pressure.3 Thrombotic microangiopathy secondary to malignant hypertension has been reported.4 It is a well-established fact that Takayasu’s arteritis can cause renovascular hypertension through its involvement of the renal artery.5 Takayasu’s involvement of the renal arteries is often bilateral and frequently ostial and proximal, usually with coexisting stenosis of the perirenal aorta.5 Cases of malignant hypertension secondary to Takayasu’s arteritis have also been reported.6.7 In our case, malignant hypertension that was triggered by bilateral renal artery stenosis due to Takayasu’s arteritis caused acute kidney injury and advanced hypertensive retinopathy. Additionally, unlike the other cases of Takayasu’s arteritis with malignant hypertension, thrombotic microangiopathy was also detected. Treatment of the underlying condition (Takayasu’s arteritis) and its complication (renal artery stenosis) was an important aspect of the management of malignant hypertension and its complications. In our case, the patient received her monthly dose of IV tocilizumab and received an adequate dose of methylprednisolone to control Takayasu’s arteritis activity. The interventional radiology department’s use of balloon dilation and stenting to treat renal artery stenosis broke the vicious cycle of malignant hypertension and treated thrombotic microangiopathy.

Informed consent

A signed informed consent for publication was obtained from the patient.

Institutional approval

Institutional approval was not required to release case details.

Disclosure

The authors report no conflict of interest in this work.

The references

1. Russo RAG, Katsicas MM. Takayasu’s arteritis. front pediatrician. 2018;6:265. doi:10.3389/fped.2018.00265

2. Chaudhry MA, Latif F. Takayasu’s arteritis and its role in renal artery stenosis. Am J Med Sci. 2013;346(4):314–318. doi:10.1097/MAJ.0b013e31827e5dad

3. Domek M, Gumprecht J, Lip GYH, Shantsila A. Malignant hypertension: does it still exist? J Hum Hypertens. 2020;34:1–4. doi:10.1038/s41371-019-0267-y

4. Shigabaki Y, Fujita T. Thrombotic microangiopathy in malignant hypertension and hemolytic uraemic syndrome (HUS)/thrombotic thrombocytopenic purpura (TTP): can we tell one from the other? Hypertens Res. 2005;28(1):89–95. doi:10.1291/hypres.28.89

5. Li Cavoli G, Mulè G, Vallone MG, Effects of Caputo F. Takayasu’s disease on the kidneys: current perspectives. Int J Nephrol Renovasc Dis. 2018;11:225–233. doi:10.2147/IJNRD.S146355

6. Wolak T, Szendro G, Golcman L, Paran E. Malignant hypertension as a presenting symptom of Takayasu’s arteritis. Mayo ClinProc. 2003;78(2):231–236. doi:10.4065/78.2.231

7. Patel B, Tiwari A, Dubey SR, Bhatt GC, Tiwari P, Bhan BD. Takayasu’s arteritis with malignant hypertension; a rare manifestation of a rare disease: about a case and review of the literature. Too Doc. 2017;47(1):60–63. doi:10.1177/0049475516648062