Renal Biopsy in Paroxysmal Nocturnal Hemoglobinuria: An Insight into the Spectrum of Morphologic Changes

Efficacy and Safety of Eculizumab in Enteroaggregative E. coli Associated Hemolytic Uremic Syndrome

BACKGROUND

Hemolytic uremic syndrome (HUS) may present atypically without the full triad of classical HUS. Eculizumab has been shown to be efficacious in complement-mediated atypical HUS and some cases of Shiga-toxin (ST) associated HUS. We report the utility of eculizumab in enteroaggregative E. coli (EAEC) associated HUS.

CASE SUMMARY

A female toddler presented with hemolytic anemia, oliguric acute kidney injury (AKI) without thrombocytopenia, and peripheral schistocytes. The stool examination for ST was negative but positive for EAEC. She required several hemodialysis sessions and received one dosage of eculizumab with rapid reversal of AKI and hemolytic markers. A kidney biopsy revealed acute tubular injury and segmental glomerular basement membrane splitting. Genetic testing was negative for complement mutations or deficiencies. A follow-up six months later showed persistently normal renal function and hematological markers.

CONCLUSION

The clinical and histological manifestations of non-ST-associated diarrheal HUS and the role of eculizumab in this condition warrant future larger studies.

A case report on clinical features, diagnosis, and treatment of rhino-orbito-cerebral mucormycosis

BACKGROUND

Rhino-orbito-cerebral mucormycosis (ROCM) is an opportunistic pathogenic fungal disease caused by the fungus mucor, and it is a life-threatening fungal infection. The ulceration on the skin of the head and neck, accompanied by rhinitis, headache, orbital inflammation, and eyelid edema, should raise a high suspicion of Mucor infection in diabetic patients with inadequately controlled blood glucose.

CASE DESCRIPTION

The clinical data of a patient with ROCM were analyzed retrospectively, and the clinical features were analyzed. The patient was admitted to the hospital with "diabetic hyperosmotic coma" after presenting with fatigue, poor appetite, and disturbances in consciousness as initial symptoms. After improving relevant examinations, controlling underlying diseases, and administering antifungal treatment, the final clinical outcome was death.

CONCLUSION

ROCM is more prevalent in patients with uncontrolled diabetes and varied clinical manifestations. The characteristic feature is an eschar-like necrosis of the local skin or mucosa. The gold criteria for diagnosis are pathology and fungal culture; imaging examination does not reveal any specific manifestations. Early diagnosis and effective treatment are the keys.

Histopathologically TMA-like distribution of multiple organ thromboses following the initial dose of the BNT162b2 mRNA vaccine (Comirnaty, Pfizer/BioNTech): an autopsy case report

Background

Coronavirus disease 2019 (COVID-19) has spread worldwide. Vaccination is now recommended as one of the effective countermeasures to control the pandemic or prevent the worsening of symptoms. However, its adverse effects have been attracting attention. Here, we report an autopsy case of multiple thromboses after receiving the first dose of the BNT162b2 mRNA vaccine (Comirnaty, Pfizer/BioNTech) in an elderly woman.

Case presentation

A 72-year-old woman with a history of diffuse large B-cell lymphoma in the stomach and hyperthyroidism received the first dose of the BNT162b2 mRNA vaccine and died 2 days later. The autopsy revealed multiple microthrombi in the heart, brain, liver, kidneys, and adrenal glands. The thrombi were CD61 and CD42b positive and were located in the blood vessels primarily in the pericardial aspect of the myocardium and subcapsular region of the adrenal glands; their diameters were approximately 5–40 μm. Macroscopically, a characteristic myocardial haemorrhage was observed, and the histopathology of the characteristic thrombus distribution, which differed from that of haemolytic uraemic syndrome and disseminated intravascular coagulation, suggested that the underlying pathophysiology may have been similar to that of thrombotic microangiopathy (TMA).

Conclusion

This is the first report on a post-mortem case of multiple thromboses after the BNT162b2 mRNA vaccine. The component thrombus and characteristic distribution of the thrombi were similar to those of TMA, which differs completely from haemolytic uraemic syndrome or disseminated intravascular coagulation, after vaccination. Although rare, it is important to consider that fatal adverse reactions may occur after vaccination and that it is vital to conduct careful follow-up.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12959-022-00418-7.

Complement Inhibition Therapy and Dialytic Strategies in Paroxysmal Nocturnal Hemoglobinuria: The Nephrologist's Opinion

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare clonal disease that presents an estimated incidence of 1.3 cases per million per year, with a prevalence of 15.9 cases per million. It is characterized by hemolysis, bone marrow dysfunction with peripheral blood cytopenia, hypercoagulability, thrombosis, renal impairment and arterial and pulmonary hypertension. Hemolysis and subsequent hemosiderin accumulation in tubular epithelium cells induce tubular atrophy and interstitial fibrosis. The origin of PNH is the somatic mutation in the X-linked phosphatidylinositol glycan class A (PIG-A) gene located on Xp22: this condition leads to the production of clonal blood cells with a deficiency in those surface proteins that protect against the lytic action of the activated complement system. Despite the increased knowledge of this syndrome, therapies for PNH were still only experimental and symptomatic, until the introduction of the C5 complement blockade agent Eculizumab. A second generation of anti-complement agents is currently under investigation, representing future promising therapeutic strategies for patients affected by PNH. In the case of chronic hemolysis and renal iron deposition, a multidisciplinary approach should be considered to avoid or treat acute tubular injury or acute kidney injury (AKI). New promising perspectives derive from complement inhibitors and iron chelators, as well as more invasive treatments such as immunoadsorption or the use of dedicated hemodialysis filters in the presence of AKI.

[Renal hemosiderosis following mechanical hemolysis: An original case report]

Renal hemosiderosis is a rare cause of acute kidney injury, but it can also lead to chronic kidney failure. We report here the case of a 73-year-old patient with acute kidney caused by a massive hemosiderosis following the proximal disinsertion of a prosthesis of the ascendant aorta with chronic aortic dissection. The kidney biopsy revealed the diagnosis, showing massive iron deposits inside the proximal tubules, especially with Perls staining and also diffuse hematic casts in the lumen of the tubules. Pathophysiology of hemosiderosis is well described, as well as protective mechanisms. This case report is one of the numerous different causes of renal hemosiderosis that can be related to genetic, infectious or mechanical hemolysis.