Ocular involvement in paediatric haemolytic uraemic syndrome

Low-molecular weight inhibitors of the alternative complement pathway

Dysregulation of the alternative complement pathway predisposes individuals to a number of diseases. It can either be evoked by genetic alterations in or by stabilizing antibodies to important pathway components and typically leads to severe diseases such as paroxysmal nocturnal hemoglobinuria, atypical hemolytic uremic syndrome, C3 glomerulopathy, and age-related macular degeneration. In addition, the alternative pathway may also be involved in many other diseases where its amplifying function for all complement pathways might play a role. To identify specific alternative pathway inhibitors that qualify as therapeutics for these diseases, drug discovery efforts have focused on the two central proteases of the pathway, factor B and factor D. Although drug discovery has been challenging for a number of reasons, potent and selective low-molecular weight (LMW) oral inhibitors have now been discovered for both proteases and several molecules are in clinical development for multiple complement-mediated diseases. While the clinical development of these inhibitors initially focuses on diseases with systemic and/or peripheral tissue complement activation, the availability of LMW inhibitors may also open up the prospect of inhibiting complement in the central nervous system where its activation may also play an important role in several neurodegenerative diseases.

Ocular involvement in STEC-associated hemolytic uremic syndrome

BACKGROUND

Hemolytic uremic syndrome (HUS) is a systemic thrombotic microangiopathy characterized by hemolytic anemia, thrombocytopenia, and variable kidney involvement. Extrarenal thrombotic microangiopathy occurs in central nervous system (CNS), colon, and other organ systems, but ocular involvement is rarely recognized. This study aimed to analyze frequency and severity of ocular involvement in STEC-HUS, and the relationship between ocular involvement and disease severity, with emphasis on CNS, kidney, and colonic disease.

METHODS

Prospective, longitudinal, observational study.

INCLUSION CRITERIA

STEC-HUS patients September 2014-January 2019. Funduscopic examination (FE) was performed within 48 h of admission. We evaluated severity of CNS disease, kidney involvement, and presence of hemorrhagic colitis (HC).

RESULTS

Ninety-nine patients were included (female 52), mean age 39.4 months (DE: 29.8; range 9-132). Thirteen patients (13.1%) had abnormal FE, 10 showing variable degrees of hemorrhagic exudates and 2 with typical Purtscher-like retinopathy. Other findings included tortuous vascularity, cotton wool spots, and transient retinal edema. CNS involvement was present in 16/99 patients, severe in 12 (75%). Abnormal FE occurred in 5/12 (31%) patients with severe CNS involvement vs. 8/87 (9.2%) with mild, moderate, or no CNS disease (p = 0.0191). Abnormal FE was present in 2/33 (6%) patients without dialysis vs. 11/66 (16.6%) requiring dialysis (p = 0.20). Finally, there were FE abnormalities in 6/20 patients with HC vs. 7/79 without HC (p = 0.012).

CONCLUSIONS

FE abnormalities were present in 13% of HUS patients. Abnormal FE significantly associated with more severe disease, including severe CNS involvement and HC. We suggest FE should be performed in severe HUS, especially in cases with severe CNS disease. A higher resolution version of the Graphical abstract is available as Supplementary information.

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 tomography features of thrombotic microangiopathy associated with atypical hemolytic-uremic syndrome]

OBJECTIVE

To evaluate structural and morphological changes in the retina using optical coherence tomography (OCT) in patients with thrombotic microangiopathy (TMA) associated with atypical hemolytic-uremic syndrome (aHUS).

MATERIAL AND METHODS

The study analyzed OCT data of 14 patients (28 eyes) with an established diagnosis of aHUS including such indicators as central retinal thickness (CRT), thickness of the retinal nerve fiver layer (RNFL), ganglion cell layer (GCL), retinal pigment epithelium (RPE), etc.

RESULTS

Patients with aHUS were noted to have an increase in CRT, paracentral acute middle maculopathy in the form of a hyperreflective defect primarily of the inner nuclear layer of paracentral localization, as well as disorganization of the RPE, which was observed statistically significantly more often compared to healthy persons (p=0.0001, p=0.001 and p=0.009 respectively). In the subgroup with thrombotic retinopathy (6 people) a statistically significant increase in CRT and peripapillary RNFL was found (p=0.004 and p=0.001) compared to patients without thrombotic retinopathy, as well as the presence of paracentral acute middle maculopathy and transudative macular retinoschisis (p=0.0001 and p=0.004). A statistically significant thinning of the peripapillary RNFL was revealed (p=0.0001) in the subgroup with symptoms of Purtscher-like retinopathy (PLR) found retrospectively (4 people) compared to patients without retrospective PLR symptoms. A statistically significant decrease in CRT was revealed (p=0.018) in the subgroup of patients receiving systemic therapy with eculizumab (5 people) compared with patients not receiving this therapy. Statistically significant correlations were recorded between the studied OCT indicators, laboratory indicators, and the level of systolic blood pressure (p<0.05).

CONCLUSION

According to OCT, paracentral acute middle maculopathy is a biomarker of thrombotic retinopathy and the activity of systemic TMA associated with aHUS. Arterial hypertension is an additional aggravating factor in the development of paracentral acute middle maculopathy and transudative macular retinoschisis. Targeted therapy with eculizumab leads to an effective decrease in CRT, which is potentially associated with regression of ischemic edema. The outcome of PLR involves thinning of peripapillary RNFL.

[Ocular manifestations of primary thrombotic microangiopathy]

The article reviews literature on ocular manifestations of primary thrombotic microangiopathy. Thrombotic microangiopathy is a clinical and morphological syndrome that characterizes a systemic disseminated lesion of the microcirculatory bed, it is a special type of vascular damage that combines thrombosis and inflammation of the vascular wall leading to occlusion of the vessel lumen, causing ischemic damage to various organs and tissues. The classic types of primary thrombotic microangiopathy are thrombotic thrombocytopenic purpura, shigatoxin-associated hemolytic uremic syndrome (STEC-HUS) and atypical hemolytic uremic syndrome. Thrombotic thrombocytopenic purpura and atypical hemolytic uremic syndrome are characterized by ischemic damage to the visual organ as a result of suspected thrombotic microangiopathy in the microcirculatory bed of the eye. The clinical picture of ocular manifestations of these diseases is similar, however the damage to the eye in the form of ischemic Purtscher-like retinopathy is more characteristic of atypical hemolytic uremic syndrome, which may be due to chronic uncontrolled activation of the alternative complement pathway in this disorder. Timely initiation of systemic therapy of the underlying disease in most cases leads to complete restoration of visual functions. A thorough ophthalmological examination of patients with these diseases is required.

Purtscher-like retinopathy in a paediatric patient with haemolytic uraemic syndrome: A case report and literature review

An 8-year-old boy presented with fever, vomits, bloody diarrhoea, and blurred vision. The patient was diagnosed with Haemolytic Uraemic Syndrome (HUS) due to the symptoms and a positive Verotoxin stool test. Funduscopic examination showed retinal involvement in both eyes, peri-papillary paleness, retinal haemorrhages, and soft "Purtscher Fleckens" exudates. A favourable outcome was achieved after hospital admission and systemic treatment. Dialysis treatment was not needed due the preserved diuresis. Although Purtscher-like retinopathy is very uncommon, ocular examination is mandatory in patients with pancreatitis, autoimmune diseases, and thrombotic microangiopathies, such as HUS.

Threatening Blindness in a Child With Typical Hemolytic Uremic Syndrome

BACKGROUND

Hemolytic uremic syndrome (HUS) is the most common cause of acute kidney failure in children younger than five years. Central nervous system involvement occurs in 15% of patients, with clinical manifestations including confusion, coma, seizures, stroke, and cortical blindness. Ocular involvement in children with HUS is rare, but retinal and choroidal hemorrhages as well as ischemic retinopathy due to thrombotic microangiopathic lesions have been documented.

PATIENT DESCRIPTION

We describe a 26-month-old girl with typical HUS who experienced severe visual loss likely resulting from cytotoxic injury of both lateral geniculate nuclei with bilateral damage to optic pathways coupled with macular thrombotic microangiopathic lesions. Her vision recovered completely within a month in conjunction with the normalization of her imaging studies.

CONCLUSIONS

Although this child's vision was severely impaired, the prognosis for this mixed visual impairment of peripheral and central origin was excellent with a full recovery.

Retinal hemorrhage and bleeding disorders in children: A review

BACKGROUND

Retinal hemorrhages (RH) are a common manifestation of abusive head trauma (AHT) resulting from acceleration-deceleration injury with or without blunt impact. Evaluation of a child with RH requires careful consideration of these differential diagnoses. The extent to which coagulopathy alone can cause RH would be useful to understand as coagulopathy may accompany AHT.

OBJECTIVE

In this systematic review, we sought to identify whether coagulopathies have been reported with RH similar to those of AHT.

METHODS

We performed a literature search for ocular manifestations of bleeding disorders in children less than 18 years old. We included clotting factor deficiencies, vitamin K deficiency, platelet function abnormalities, thrombocytopenia, disseminated intravascular coagulation (DIC), and trauma induced coagulopathy (TIC). We included only pediatric reports of intraocular bleeding or documented eye examinations that indicated no hemorrhages. We then re-examined cases for ocular and systemic findings that could potentially mimic abuse.

RESULTS

Our initial search yielded 816 results. Sixty-one articles met our inclusion criteria. Of these, there were 32 children within the AHT age range (less than 5 years old) who had RH and concomitant coagulopathy. Only 5 cases might potentially be confused for abuse. Of these, no classic characteristics of RH from abuse such as retinoschisis or retinal folds were found. Systemic features were inconsistent with AHT.

CONCLUSIONS

The presence of coagulopathy alone does not rule out the possibility that the child has been abused. Coagulopathy alone has not been reported as an etiology of RH that are consistent with AHT, especially when other findings are present.

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.

Purtscher-like retinopathy in a paediatric patient with haemolytic uraemic syndrome: A case report and literature review

An 8-year-old boy presented with fever, vomits, bloody diarrhea, and blurred vision. The patient was diagnosed with haemolytic uraemic syndrome (HUS) due to the symptoms and a positive verotoxin stool test. Funduscopic examination showed retinal involvement in both eyes, peri-papillary paleness, retinal haemorrhages, and soft Purtscher «fleckens» exudates. A favourable outcome was achieved after hospital admission and systemic treatment. Dialysis treatment was not needed due the preserved diuresis. Although Purtscher-like retinopathy is very uncommon, ocular examination is mandatory in patients with pancreatitis, autoimmune diseases, and thrombotic microangiopathies, such as HUS.

Two cases of severe Purtscher-like retinopathy demonstrating recurrence and progression to neovascularization and vitreous hemorrhage

Purpose

To report the clinical course of two cases with Purtscher-like retinopathy (PLR), associated with peritoneal dialysis (PD), demonstrating disease recurrence and progression to neovascularization and vitreous hemorrhage.

Observations

Case 1 (45-year old woman) experienced acute bilateral vision loss. Medical history included hypertension, end-stage renal failure (ESRF), PD, and obstructive sleep apnea. Visual acuity (VA) was 20/100 OD, 20/80 OS. Fundus findings were pathognomonic for PLR and included white streaks within arterioles. Nine months later, repeat imaging demonstrated disease recurrence and progression, including increased ischemia and new retinal neovascularization. The patient was managed with pan-retinal photocoagulation, sleep apnea treatment, and oral corticosteroids. Four months later, VA remained stable without additional progression.

Case 2 (74-year old woman) experienced acute bilateral vision loss. Medical history included hypertension, ESRF, and PD, complicated by peritonitis. VA was 20/25 OD, 20/32 OS. Fundus findings were pathognomonic for PLR and included white streaks within arterioles. Three months later, further acute vision loss occurred, coinciding with recurrent peritonitis. Repeat imaging revealed disease recurrence and progression, including severely increased retinal ischemia. The PD catether was removed and the patient converted to hemodialysis. Bilateral vitreous hemorrhage later complicated the course.

Conclusions and importance

PLR can occur in association with PD, particularly in acute peritonitis. Contrary to classical descriptions, PLR may take a chronic and progressive course, with increasing ischemia and progression to neovascularization or vitreous hemorrhage. Increased surveillance for complications is recommended and treatment of neovascularization may be required.

[Optical coherence tomography angiography in the diagnosis of retinal microangiopathy in atypical hemolytic-uremic syndrome (a case report)]

The article describes a clinical case of acute macular neuroretinopathy and «chronic» paracentral acute middle maculopathy in a patient with atypical hemolytic-uremic syndrome - an orphan disease characterized by systemic thrombosis in the vessels of the microcirculatory bed due to chronic uncontrolled activation of the alternative complement pathway. Optical coherence tomography angiography data confirm the ischemic nature of the disease with localization in the deep vascular plexus of the retina in acute macular neuroretinopathy and in the superficial vascular plexus of the retina in «chronic» paracentral acute middle maculopathy. The use of modern diagnostic methods, including optical coherence tomography angiography, can help improve detection of the pathology and expand its understanding in severe microangiopathic syndromes, which include atypical hemolytic-uremic syndrome.

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

RATIONALE

To report a rare case of severe atypical hemolytic-uremic syndrome (HUS) in a patient who presented with vitreous hemorrhage and tractional retinal detachment (TRD) in both eyes. To our knowledge, this is the first reported case of atypical HUS complicated with bilateral TRD in the literature.

PATIENT CONCERNS

A 20-year-old man with atypical HUS demonstrated bilateral visual acuity of hand motion at 30 cm.

DIAGNOSES

Dilated fundus examination revealed diffuse intraretinal hemorrhage with vascular engorgement, neovascularization of the disc, and neovascularization elsewhere bilaterally. Fluorescein angiography revealed bilateral proliferative retinopathy, retinal hemorrhage, and a large nonperfusion area with extensive neovascularization. Intravitreal antivascular endothelial growth factor (ranibizumab) injection was administered in both eyes, but his ophthalmic condition did not improve, and TRD developed bilaterally. Therefore atypical HUS complicated with bilateral TRD was diagnosed.

INTERVENTIONS

Pars plana vitrectomy was performed with panretinal photocoagulation and silicone oil tamponade in the right eye.

OUTCOMES

After the pars plana vitrectomy of right eye, the retina was well-attached after surgery, but visual acuity remained poor. Visual evoked potential examination showed poor waveforms bilaterally, which suggested ischemic optic neuropathy.

LESSONS

Atypical HUS can cause systemic thrombotic microangiopathy, resulting in ischemic retinal changes. These ischemic retinal changes can then cause hypoxia, which triggers production of angiogenic factors and subsequently causes retinal vascular hyperpermeability, retinal and vitreous neovascularization, fibrovascular proliferation, vitreous hemorrhage, and TRD, in a manner similar to that of other ischemia-induced proliferative retinopathies. Despite successful surgery in the right eye, our patient's visual acuity did not improve, possibly because of severe and generalized ischemia of intraocular tissue, which resulted in ischemic optic neuropathy.

Extra-renal manifestations of atypical hemolytic uremic syndrome

Atypical hemolytic uremic syndrome (aHUS) is a rare and complex disease resulting from abnormal alternative complement activation with a wide range of clinical presentations. Extra-renal manifestations of aHUS can involve many organ systems, including the peripheral and central nervous, gastrointestinal, cardiovascular, integumentary, pulmonary, as well as the eye. While some of these extra-renal manifestations occur in the acute phase of aHUS, some can also occur as long-term sequelae of unopposed complement activation. Extra-renal symptoms are observed in approximately 20% of patients with aHUS, with the incidence of specific organ system complications ranging from a few case reports to 50% of described patients. Careful monitoring for extra-renal involvement is critical in patients with aHUS, as prompt evaluation and management may decrease the risk of high morbidity and mortality associated with aHUS.

Complement Factor H Mutation W1206R Causes Retinal Thrombosis and Ischemic Retinopathy in Mice

Single-nucleotide polymorphisms and rare mutations in factor H (FH; official name, CFH) are associated with age-related macular degeneration and atypical hemolytic uremic syndrome, a form of thrombotic microangiopathy. Mice with the FH W1206R mutation (FH^R/R) share features with human atypical hemolytic uremic syndrome. Herein, we report that FH^R/R mice exhibited retinal vascular occlusion and ischemia. Retinal fluorescein angiography demonstrated delayed perfusion and vascular leakage in FH^R/R mice. Optical coherence tomography imaging of FH^R/R mice showed retinal degeneration, edema, and detachment. Histologic analysis of FH^R/R mice revealed retinal thinning, vessel occlusion, as well as degeneration of photoreceptors and retinal pigment epithelium. Immunofluorescence showed albumin leakage from blood vessels into the neural retina, and electron microscopy demonstrated vascular endothelial cell irregularity with narrowing of retinal and choroidal vessels. Knockout of C6, a component of the membrane attack complex, prevented the aforementioned retinal phenotype in FH^R/R mice, consistent with membrane attack complex-mediated pathogenesis. Pharmacologic blockade of C5 also rescued retinas of FH^R/R mice. This FH^R/R mouse strain represents a model for retinal vascular occlusive disorders and ischemic retinopathy. The results suggest complement dysregulation can contribute to retinal vascular occlusion and that an anti-C5 antibody might be helpful for C5-mediated thrombotic retinal diseases.

Progressive Retinal Findings in Hemolytic Uremic Syndrome

Ocular involvement in hemolytic uremic syndrome is rare and in most cases presents with retinal ischemia, hemorrhages, and neovascularization. The authors describe the progression of retinal involvement as a rare complication of typical hemolytic uremic syndrome in a 2-year-old boy. Progression of retinal findings were demonstrated with serial fundus photographs. All children who develop hemolytic uremic syndrome have an early ocular consultation and regular ophthalmic follow-up. Early and regular ophthalmic examinations will be useful to expand the understanding of this rare ocular complication and to guide treatment options. [J Pediatr Ophthalmol Strabismus. 2018;55:e49-e51.].

[Ocular thrombotic microangiopathy in atypical hemolytic-uremic syndrome (a clinical case study)]

The article presents a clinical observation of ocular thrombotic microangiopathy in atypical hemolytic-uremic syndrome - a rare genetic disease characterized by systemic thrombosis caused by uncontrolled activation of alternative complement pathway. A typical manifestation of this ocular lesion in this disease is bilateral Purtscher-like retinopathy. Timely diagnostics of atypical hemolytic-uremic syndrome, including ophthalmologic examination, determines the early start of a highly effective pathogenetic therapy with complement inhibitor eculizumab.

Shiga Toxins Induce Apoptosis and ER Stress in Human Retinal Pigment Epithelial Cells

Shiga toxins (Stxs) produced by Shiga toxin-producing bacteria Shigella dysenteriae serotype 1 and select serotypes of Escherichia coli are the most potent known virulence factors in the pathogenesis of hemorrhagic colitis progressing to potentially fatal systemic complications such as acute renal failure, blindness and neurological abnormalities. Although numerous studies have defined apoptotic responses to Shiga toxin type 1 (Stx1) or Shiga toxin type 2 (Stx2) in a variety of cell types, the potential significance of Stx-induced apoptosis of photoreceptor and pigmented cells of the eye following intoxication is unknown. We explored the use of immortalized human retinal pigment epithelial (RPE) cells as an in vitro model of Stx-induced retinal damage. To the best of our knowledge, this study is the first report that intoxication of RPE cells with Stxs activates both apoptotic cell death signaling and the endoplasmic reticulum (ER) stress response. Using live-cell imaging analysis, fluorescently labeled Stx1 or Stx2 were internalized and routed to the RPE cell endoplasmic reticulum. RPE cells were significantly sensitive to wild type Stxs by 72 h, while the cells survived challenge with enzymatically deficient mutant toxins (Stx1A⁻ or Stx2A⁻). Upon exposure to purified Stxs, RPE cells showed activation of a caspase-dependent apoptotic program involving a reduction of mitochondrial transmembrane potential (Δψ_m), increased activation of ER stress sensors IRE1, PERK and ATF6, and overexpression CHOP and DR5. Finally, we demonstrated that treatment of RPE cells with Stxs resulted in the activation of c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38MAPK), suggesting that the ribotoxic stress response may be triggered. Collectively, these data support the involvement of Stx-induced apoptosis in ocular complications of intoxication. The evaluation of apoptotic responses to Stxs by cells isolated from multiple organs may reveal unique functional patterns of the cytotoxic actions of these toxins in the systemic complications that follow ingestion of toxin-producing bacteria.

Ocular involvement in atypical haemolytic uraemic syndrome

CASE REPORT

The case is presented of a young man with an atypical haemolytic-uraemic syndrome (aHUS), complicated with bilateral serous retinal detachment, cotton wool spots, and a branch artery occlusion. Treatment with plasmapheresis, haemodialysis and systemic eculizumab led to the blood and urine parameters returning to normal, as well as resolution of the retinal anomalies. Genetic analysis show both mutations in complement factor H and C3.

DISCUSSION

Haemolytic-uraemic syndrome (HUS) is a thrombotic microangiopathy characterised by microangiopathic haemolytic anaemia, thrombocytopenia, and acute renal failure. Atypical HUS is caused by genetic mutation of complement system. Ocular involvement is an unusual manifestation of this rare syndrome.

Reversal of threatening blindness after initiation of eculizumab in Purtscher-like retinopathy secondary to atypical hemolytic uremic syndrome

Purtscher-like retinopathy, a rare manifestation of systemic thrombotic microangiopathy, is a potentially visually debilitating condition with no effective proven treatment. Distinct pathogenic pathways have been proposed as etiological factors. We revisit the etiology of Purtscher-like retinopathy based on the rapid response and profound visual improvement after initiation of systemic intravenous eculizumab, an inhibitor of the complement cascade, in a patient with Purtscher-like retinopathy secondary to familial atypical hemolytic uremic syndrome (aHUS) due to a mutation in complement factor H. We hypothesize that the efficacy of eculizumab in this patient provides evidence for pathogenic events in the retina similar to those encountered in the renal microvasculature of aHUS patients, namely complement-mediated thromboembolization as a result of activation of the complement cascade in endothelial cells with release of tissue factor and development and amplification of a procoagulant state. To the best of our knowledge, this is the first report in the literature of eculizumab as an effective therapeutic strategy in Purtscher-like retinopathy.

Health-related quality of life and mental health in parents of children with hemolytic uremic syndrome

BACKGROUND

Little is known about health-related quality of life (HRQoL) and mental health of parents having children with a history of hemolytic uremic syndrome (HUS).

METHODS

This study included 63 mothers and 58 fathers of a cohort of 63 HUS-affected children. At assessment, the mean time since a child experienced an acute episode of HUS was 6.4 years. Parental HRQoL, mental health and posttraumatic stress disorder (PTSD) were assessed with standardized self-report questionnaires. Medical data were extracted from patients' hospital records.

RESULTS

The HRQoL and mental health of both the mothers and fathers were not impaired compared to normative data. However, a shorter time since a child's acute HUS episode was a significant predictor of lower HRQoL among the mothers, while no such effect was found among the fathers. Two fathers (3%), but no mothers, met the criteria for a diagnosis of HUS-related full PTSD; one father (2%) and four mothers (6%) met the criteria for a diagnosis of HUS-related partial PTSD.

CONCLUSIONS

Our study shows that most parents of our study sample were doing well in terms of HRQoL and mental health, although a small number met the criteria for full or partial PTSD diagnosis due to their child's HUS. We therefore recommend that healthcare providers pay special attention to parents regarding PTSD symptoms during the clinical follow-up of a HUS-affected child since some parents may benefit from psychological support.

[Vitrectomy for retinal proliferation in childhood following hemolytic uremic syndrome]

The formation of retinal membranes can occur due to a variety of reasons but they are most commonly idiopathic due to the aging process. In addition, epiretinal and subretinal membranes can be formed after severe infections. The present case description shows the appearance of a retinal membrane after hemolytic uremic syndrome caused by Shiga toxin positive E. coli. The question arose whether the patient would benefit from vitrectomy with membrane peeling because of the presence of both epiretinal and subretinal gliotic changes. After the operation on the more severely affected right eye a morphological improvement could be achieved so that an operation on the left eye was also recommended. Judging by the course of this case vitrectomy with membrane peeling seems to be a useful instrument even for the simultaneous presence of subretinal and epiretinal membranes.

Bilateral tractional retinal detachment in a patient with hemolytic-uremic syndrome

Hemolytic uremic syndrome (HUS) is a thrombotic microangiopathy characterized by hemolytic anemia, acute kidney injury, and thrombocytopenia. Ophthalmic manifestations of HUS range from mild, including scattered intraretinal hemorrhages, to severe, including a Purtscher-like retinopathy and iris and optic disk neovascularization (NVD). We report the case of a 23-month-old girl with severe HUS who presented with bilateral dense vitreous hemorrhage. During vitrectomy, optic disk neovascularization and funnel-shaped, tractional detachments of both retinas were observed. To our knowledge, this is the first reported case of tractional retinal detachment in the context of HUS.

Recurrent ocular involvement in pediatric atypical hemolytic uremic syndrome

Atypical hemolytic uremic syndrome (HUS) is a subtype of thrombotic microangiopathy associated with complement alternative pathway dysregulation. It is clinically characterized by a relapsing course and a poor prognosis. Multiple organ systems are commonly affected by thrombotic microangiopathy in pediatric atypical HUS; however, ocular involvement is rarely reported. The case of an 11-year-old girl diagnosed as having atypical HUS who presented with bilateral central retinal vein occlusions with macular subhyaloid hemorrhage during her initial onset and ophthalmoplegia, diplopia, and optic disc edema during her relapsing episode 1 year later is described. All ocular manifestations occurred in the convalescence phase of atypical HUS. No other extrarenal complications were found and full recovery was achieved following typical treatment for atypical HUS (ie, plasma infusion, steroid, and supportive therapy). This is thought to be the first reported case of recurrent ocular involvement in pediatric atypical HUS.

Shiga Toxin/Verocytotoxin-Producing Escherichia coli Infections: Practical Clinical Perspectives

Escherichia coli strains that produce Shiga toxins/verotoxins are rare, but important, causes of human disease. They are responsible for a spectrum of illnesses that range from the asymptomatic to the life-threatening hemolytic-uremic syndrome; diseases caused by E. coli belonging to serotype O157:H7 are exceptionally severe. Each illness has a fairly predictable trajectory, and good clinical practice at one phase can be inappropriate at other phases. Early recognition, rapid and definitive microbiology, and strategic selection of tests increase the likelihood of good outcomes. The best management of these infections consists of avoiding antibiotics, antimotility agents, and narcotics and implementing aggressive intravenous volume expansion, especially in the early phases of illness.

Systematic review of Purtscher's and Purtscher-like retinopathies

PURPOSE

(1) To describe the clinical characteristics of Purtscher and Purtscher-like retinopathies, including etiologies, fundoscopic signs, results of complementary investigation, treatments, and outcomes. (2) To compare visual acuity (VA) of patients receiving corticosteroids for PuR compared with observation.

METHODS

Systematic review of several databases (1980-2010): Medline, EMBASE, ISI, EBSCO, Science Direct and Google Scholar. Study selection criteria included: (A) Studies of PuR with ophthalmology assessments; (B) ≥3 of 5 diagnostic criteria of PuR; (C) Quantified VA at presentation. For quantitative assessment (purpose 2), we selected only studies that reported whether corticosteroids were administered, and with vision assessments after at least 1 month.

RESULTS

(1) From 670 studies initially found, 40 were included (68 cases, 110 eyes): 1 prospective, 5 case series, and 34 case reports. Mean VA at presentation was 1.3 logMAR (logarithm of the minimum angle of resolution) (<20/200; range: 20/20-light perception). Purtscher flecken were underreported. Trauma and acute pancreatitis were the most frequent etiologies. There were six deaths, all with systemic associations. (2) There was no statistically significant difference between VA improvement for patients treated with corticosteroids compared with observation. Visual prognostic factors identified included etiology (pancreatitis and trauma were associated with higher probability of visual improvement) and male gender.

CONCLUSION

Due to limitations of case reports and series, the presented data are only useful as broad characterizations of the clinical course of PuR. Further studies, possibly including trials to assess the effectiveness of corticosteroids use, and larger prospective cohort studies, are necessary, but may not be feasible to conduct.

Thrombotic microangiopathy and Purtscher-like retinopathy as a rare presentation of juvenile dermatomyositis

Juvenile dermatomyositis is a rare systemic vasculopathy that may sometimes present with acute complications. We report here the case of a 7-year-old boy with severe dermatomyositis associated with thrombocytopenia and blurry vision. The presence of schistocytosis and the secondary occurrence of hemolytic anemia were consistent with a diagnosis of thrombotic thrombocytopenic purpura (TTP). Further investigations demonstrated the association of TTP with muscular microangiopathy and Purtscher-like retinopathy. Retinal and hematologic involvements dramatically improved after the initiation of plasma exchange in emergency. This report emphasizes that early recognition of TTP and prompt plasmapheresis are important in a child with severe juvenile dermatomyositis associated with thrombocytopenia.

Neovascularization in Purtscher's retinopathy

We report a case of neovascularization secondary to Purtscher's retinopathy that showed minimal improvement with photocoagulation treatment. A 14-year-old boy with a history of cerebellar medulloblastoma presented with blurry vision and floaters after being struck by a motor vehicle while riding his bike. At presentation, visual acuity was 20/400 in his right eye and counting fingers in his left eye. Fundus examination showed disk edema, retinal whitening, and retinal hemorrhages in both eyes. Optical coherence tomography demonstrated thinning of the temporal retina and disruption of the inner segment-outer segment junction of the photoreceptor layer in the right eye and thickening and edema of the nasal macula, as well as a central foveal hyper-reflectivity, in the left eye. At the initial visit, there was no ischemia or neovascularization (NV). One month later, the patient developed NV of the disk and ischemia in the mid-periphery of the left eye. The patient underwent treatment with pan-retinal photocoagulation. The NV regressed, but visual outcome remained poor at his 5-month follow-up visit.