Screening important for co-occurring PNH, aplastic anemia: Case study
Early screening for comorbidities may prevent acute complications
Early screening for paroxysmal nocturnal hemoglobinuria (PNH) and aplastic anemia — two bone marrow disorders that often occur together — is important to prevent acute and serious complications, according to a recent case study.
Aplastic anemia affects the stem cells in the bone marrow that give rise to new blood cells.
“It is imperative that [co-occurring bone marrow disorders] be screened for and diagnosed early on to prevent the acute complications,” researchers wrote.
The report, “Attack of the Clones: A Patient With Untreated Aplastic Anemia Presenting With Classical Paroxysmal Nocturnal Hemoglobinuria,” was published in the journal Cureus.
PNH and plastic anemia are disorders affecting the blood
PNH is an acquired disorder caused by mutations in hematopoietic stem cells (HSCs), which are found in the bone marrow and are responsible for giving rise to new blood cells. As a result of these mutations, new blood cells become more susceptible to being attacked and destroyed by the body’s immune system. It’s their destruction over time that ultimately leads to disease symptoms.
Aplastic anemia (AA) is another disorder that affects HSCs in the bone marrow. In AA, the immune system directly destroys these cells, ultimately resulting in low blood cell counts, which causes symptoms similar to PNH. In addition to having similar symptoms, PNH and AA commonly co-occur, and people with one of the disorders are more likely to develop the other.
Here, researchers in Texas described the case of a 29-year-old man who went to the hospital due to weakness and nausea that had persisted intermittently for a week. The man had been diagnosed with AA via a bone marrow biopsy in 2018, but had not received any treatment for the condition at the time.
“Despite our patient having a history of AA, he denied having ever received immunosuppression that leads to clinical remission in a large proportion of patients,” the researchers wrote. “Whether this was due to patient choice or resource limitations, the case exemplifies the health disparities present in the US-Mexico border region and accentuates the need to identify acute complications of chronic disease in this vulnerable patient population.”
Upon examination at the researchers’ clinic, the man was noted to be unusually pale — a common sign of low red blood cell counts. A battery of diagnostic tests were then performed, including blood tests, a bone marrow biopsy, and flow cytometry.
It is imperative that [co-occurring bone marrow disorders] be screened for and diagnosed early on to prevent the acute complications.
Soliris gradually eased patient’s symptoms
Results were consistent with the previous diagnosis of AA, and flow cytometry also confirmed the diagnosis of co-occurring PNH: about 10% of the patient’s blood cells were lacking a surface protein that is typically absent in PNH.
The man was initially treated with the immune-suppressing medicine cyclosporine, but his condition did not improve. He was then treated with Soliris (eculizumab), which gradually eased his symptoms.
Soliris is an approved treatment for PNH that works by blocking the activation of the complement system, the part of the immune system that attacks and destroys blood cells in PNH. Soliris is sold by AstraZeneca, which was not involved with this study.
“Future studies should investigate the risks and benefits of adding anti-complement in AA patients who screen positive for PNH,” the researchers wrote.