Bilateral proliferative retinopathy and ischemic optic neuropathy in a patient with atypical hemolytic-uremic syndrome: A case report

Complement-mediated thrombotic microangiopathy on a background of Alport syndrome: A case report

Here we present a case of complement-mediated thrombotic microangiopathy (TMA) in a patient who has a background of Stage 5 chronic kidney disease secondary to Alport syndrome. We explain our approach to the diagnosis of TMA, especially the reliance on non-renal manifestations of TMA and the role of kidney biopsy given there was a background of advanced kidney impairment at baseline.

Hemolytic Uremic Syndrome: A COVID-19 Vaccine Reaction Case Report

The World Health Organization declared the Coronavirus disease of 2019 (COVID-19) a public health emergency of international concern on 30 January 2020, and a pandemic on 11 March 2020. Vaccines have proven to be vital in the effort to control and possibly eventually eradicate this viral infection. There have been reports of thromboembolic events associated with the use of vaccine but from available information, no reported case of atypical Hemolytic Uremic syndrome (HUS) in a black male has been described. We report a case of a 43-year-old black male Sub-Saharan African c5dwho presented with chills, fever, and generalized body aches of 3 days duration after receiving the second booster dose of the COVID-19 vaccine. He developed thrombocytopenia, hemolytic anaemia, and acute kidney injury on admission, and an initial diagnosis of malaria was made. He was managed with parenteral artesunate and then oral artemether/lumefantrine. His hemolytic anaemia was thought to be from malaria-associated hemolysis. This diagnosis was however later re-evaluated to hemolytic uremic syndrome and managed with 50mg daily oral prednisolone which resolved, and he resumed work a week later. Although mass vaccination is a key strategy to control the spread of COVID-19, critical observations should be made to confirm the risk of trigger for abnormal complement activation. Further observations should be made especially if it is a chimpanzee adenovirus-vectored vaccine.

Proliferative retinopathy and retinal detachment in pediatric atypical hemolytic uremic syndrome

We report the case of a 14-year-old boy with history of microangiopathic hemolytic crises secondary to atypical hemolytic uremic syndrome presenting with new-onset decreased vision, flashes, and floaters in his left eye. The patient had a history of chronic retinal detachment in the right eye and retinal neovascularization in the left eye treated with panretinal photocoagulation at age 5. He was now found to have a new combined tractional-rhegmatogenous retinal detachment in the left eye. Despite surgical reattachment of the retina, he had progressive retinal and optic nerve ischemia, with resultant left eye visual acuity of light perception. To our knowledge, this is the first reported case of proliferative retinopathy and tractional and rhegmatogenous retinal detachments in a pediatric patient with atypical hemolytic uremic syndrome.

Retinal findings in glomerulonephritis

The complement system is part of the innate immune system activated by three distinct pathways: classical, lectin and alternative. It is also involved in retinal development and homoeostasis. Dense deposit disease is a rare renal disease associated with mutations in Complement factor H and overactivity of the alternative complement pathway. As well as glomerulonephritis, many affected individuals have retinal drusen and may be at risk of vision loss due to macular atrophy or choroidal neovascularisation. We discuss the reclassification of dense deposit disease as a type of C3 glomerulonephropathy, and hypothesise on the mechanisms of retinal abnormalities. Drusen have also been described in individuals with other types of glomerulonephritis involving abnormalities of the classical (membranoproliferative glomerulonephritis type 1) or lectin (IgA nephropathy, lupus nephritis) complement pathways. Although drusen are found in abnormalities of all three complement pathways, the age at onset, aetiology, and the threat to vision differs. This review describes drusen and other retinal abnormalities associated with the glomerulonephritides due to abnormal activation in each of the three complement activation pathways, and provides the first report of drusen occurring in a patient with the recently reclassified C3 glomerulonephritis with homozygous variant V62I in complement factor H. Optometric management of young patients presenting with retinal drusen is discussed, and complement-based therapies for visual loss are reviewed.

Occlusive retinal vasculopathy with macular branch retinal artery occlusion as a leading sign of atypical hemolytic uremic syndrome - a case report

BACKGROUND

Hemolytic Uremic Syndrome (HUS) is a rare disorder characterized by the triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute renal failure, considered within the group of thrombocytic microangiopathies. Ocular complications in HUS are very rare. Here, we report an adult patient who suffered from acute onset of paracentral scotoma, caused by branch retinal artery occlusion (BRAO), as a leading symptom of atypical HUS.

CASE PRESENTATION

A 39-year-old healthy male was lately diagnosed with essential hypertension and mild renal impairment. He complained about acute onset of central scotoma in his left eye. Fundus examination revealed marked narrowing of retinal vessels, cotton wool spots and few retinal hemorrhages in both eyes. The patient was diagnosed with bilateral ischemic retinal vasculopathy and acute macular BRAO in his left eye. Workup revealed thrombocytopenia, worsening renal failure. Renal biopsy showed signs of chronic thrombotic microangiopathy. The patient was diagnosed with atypical HUS (aHUS) and started on plasmapheresis, together with eculizumab. As his condition continued to worsen, he was put on renal replacement therapy. Due to a persistent monoclone of IgG1, the patient underwent bone marrow biopsy which revealed Monoclonal Gammopathy of renal significance, triggering a HUS and treatment was initiated accordingly. Two months after initial presentation, the patient developed neovascularization of the optic disc (NVD) in his left eye, and was treated with 3 monthly intravitreal bevacizumab injections with complete regression of the NVD. The patient suffered from myocardial infarction in the later course and was lost for follow-up. He returned 11 months after the last bevacizumab injection because of sudden loss of vision in his left eye caused by a dense vitreous hemorrhage. Biomicroscopy revealed a new NVD in his right eye. The patient underwent panretinal photocoagulation in both eyes with regression of neovascularization. Vision improved and remained 20/20 in both eyes.

CONCLUSION

We present a case report showing retinal ischemia can be linked with aHUS. As clinal diagnosis might be challenging, physicians should be aware of the rare ocular manifestations of this devastating multi-organ disease. In case of retinal ischemia, panretinal photocoagulation should be initiated soon to avoid blinding complications.