Malignant hypertension and interferon-beta: a case report

Thrombotic Microangiopathy after a 15-year Treatment with Interferon Beta-1b in a Patient with Multiple Sclerosis: A Case Report and Review of Literature

A 54-year-old woman with multiple sclerosis treated with interferon-β (IFN-β)-1b for 15 years presented with sustained hypertension (240/124 mmHg) and retinal bleeding. She had proteinuria, anemia, thrombocytopenia, elevated serum creatinine levels, and haptoglobin depletion. Intravenous nicardipine stabilized her blood pressure, but her renal function and platelet count deteriorated. The initial disintegrin-like metalloprotease with thrombospondin type 1 motifs 13 (ADAMTS13) activity was 28% of normal without its inhibitor. The subsequent peripheral appearance of schistocytes suggested thrombotic microangiopathy (TMA). After IFN-β-1b cessation, the platelet count increased, and the blood pressure stabilized. The ADAMTS13 activity normalized, although the creatinine level did not. TMA may develop after the long-term use of IFN-β without adverse events.

A case report of late-onset atypical Hemolytic Uremic Syndrome during interferon beta in multiple sclerosis: Open issues in literature review

BACKGROUND AND AIMS

Interferon beta (IFNβ) is a well-established first-line therapy for relapsing-remitting multiple sclerosis (RRMS) patients and remains the most widely prescribed agent. Atypical hemolytic uremic syndrome (aHUS) represents a rare but severe adverse effect (AE) that could occur even after many years from the beginning of IFNβ therapy. Eculizumab is currently approved for treatment of aHUS and recently for neuromyelitis optica spectrum disorder (NMOSD) with aquaporin-4 antibodies (AQP4-IgG). In this article, we report the case of the latest onset of IFNβ-related aHUS experienced by an MS patient and we briefly review the literature on this topic.

METHODS

We performed a systematic review of the literature using PubMed, and we performed a retrospective analysis of RRMS patients that received IFNβ-1a in our center and developed thrombotic microangiopathy (TMA). From this search, we identified only one patient.

RESULTS

In the published literature, we identified 24 MS patients who received IFNβ as disease-modifying treatment (DMT) and then developed thrombotic microangiopathy with kidney injury. The aHUS has been diagnosed in 6, all received IFNβ-1a and the latest onset was after 15 years. We report a case of a 39-year-old man affected by RRMS who assumed IFNβ-1a since 1999. In July 2018, he developed an IFNβ-related aHUS. After the failure of plasma exchange, he underwent eculizumab, with an improvement of glomerular filtration rate and without new signs of MS activity.

CONCLUSION

To our knowledge, this case represents the latest onset of IFNβ-related aHUS in MS patients. Up to now, there are not literary reports about the possibility to reintroduce a DMT as add-on therapy to eculizumab.

Malignant hypertension: diagnosis, treatment and prognosis with experience from the Bordeaux cohort

BACKGROUND

Malignant hypertension, the most severe form of hypertension, is defined by high blood pressure and acute ischemic organ damage. It has a worse prognosis than other forms of hypertension, especially in black patients. New tools to assess organ damage, especially that of the heart and brain, are now available and may contribute to a better evaluation of these patients. This report improves knowledge of the characteristics of involved organs to facilitate diagnosis and to evaluate the effectiveness of our treatment protocol.

METHOD

The Bordeaux registry, started in 1995, recruited 168 patients. In addition to evaluations of their eyes and kidneys, these patients had a systematic evaluation of their hearts with ECG and echocardiography and, since 2007, a systematic brain MRI. Blood pressure was lowered with a protocol based on blockers of the renin-angiotensin system started at a very low-dose with forced titration over 48 h. Only an oral route was used for antihypertensive medication.

RESULTS

Systematic MRIs found significant brain damage in 93% of patients. Heart involvement was highly prevalent: 82% had left ventricular mass more than 60 g/m, and 56% had systolic dysfunction (estimated by global longitudinal strain). Renal involvement and thrombotic microangiopathy were respectively present in 55 and 15% of patients. Median follow-up was 48 months. Renal survival at 5 years was 90.8%, similar to other studies.

CONCLUSION

Malignant hypertension is a systemic disease causing severe damage to the brain, heart, kidneys and eyes, even in absence of symptoms. Renin-angiotensin system blockers seem to be the cornerstone of treatment.

Thrombotic microangiopathy induced by interferon beta in patients with multiple sclerosis: three cases treated with eculizumab

BACKGROUND

Interferon-beta (IFN-beta) is one of the most widely prescribed medications for relapsing-remitting multiple sclerosis (RRMS). IFN-related thrombotic microangiopathy (TMA) is a rare but severe complication, with a fulminant clinical onset and a possibly life-threatening outcome that may occur years after a well-tolerated treatment with IFN. Most patients evolve rapidly to advanced chronic kidney disease and eventually to renal failure.

METHODS

We performed a retrospective analysis of TMA cases diagnosed and managed in our Nephrology Department from 2010 to 2015, and performed a literature review of IFN-beta-induced TMA.

RESULTS

Three cases of TMA among patients treated with IFN-beta were identified who did not show any renal improvement following conventional therapy: IFN withdrawal and plasma exchange (PE, range 8-18) sessions. All of them responded favourably to eculizumab, with progressive clinical and renal improvement, allowing dialysis discontinuation, without recurrence of TMA during a long-term follow-up (range 1-5 years).

CONCLUSIONS

TMA is a recognized severe complication in RRMS patients treated with IFN-beta. Withdrawal of IFN and treatment with PE, steroids or rituximab did not improve the poor renal prognosis in our three patients and in all the previously described cases in the literature. In our experience, eculizumab had a strikingly favourable effect on renal recovery, suggesting a role of IFN-beta as a trigger in complement-mediated TMA. Neurologists and nephrologists should be vigilant to this complication to prevent possibly irreversible renal damage.

Type I interferon causes thrombotic microangiopathy by a dose-dependent toxic effect on the microvasculature

Many drugs have been reported to cause thrombotic microangiopathy (TMA), yet evidence supporting a direct association is often weak. In particular, TMA has been reported in association with recombinant type I interferon (IFN) therapies, with recent concern regarding the use of IFN in multiple sclerosis patients. However, a causal association has yet to be demonstrated. Here, we adopt a combined clinical and experimental approach to provide evidence of such an association between type I IFN and TMA. We show that the clinical phenotype of cases referred to a national center is uniformly consistent with a direct dose-dependent drug-induced TMA. We then show that dose-dependent microvascular disease is seen in a transgenic mouse model of IFN toxicity. This includes specific microvascular pathological changes seen in patient biopsies and is dependent on transcriptional activation of the IFN response through the type I interferon α/β receptor (IFNAR). Together our clinical and experimental findings provide evidence of a causal link between type I IFN and TMA. As such, recombinant type I IFN therapies should be stopped at the earliest stage in patients who develop this complication, with implications for risk mitigation.