Immunophenotypic challenges in diagnosis of CD79a negativity in a patient with B acute lymphoblastic leukemia harboring intrachromosomal amplification of chromosome 21: a case report

BACKGROUND

Being expressed in all stages of B-cell development and having a significant value on the European Group for the Immunological Characterization of Acute Leukemias scoring system, CD79a is considered as an excellent pan-marker for lineage assignment of B cells by flow cytometry. Therefore, any lack or decrease in CD79a expression makes the diagnosis of B acute lymphoblastic leukemia cases very challenging, especially in developing country laboratories where flow cytometry analyses are not always available and, when they are, they are limited in the number of markers used for lineage assignment. Since this case is potentially interesting, we report a B acute lymphoblastic leukemia case with a lack of expression CD79a associated with intrachromosomal amplification of chromosome 21 genetic abnormality. We further discuss the practical challenges in the diagnosis of this case.

CASE PRESENTATION

We present the case of an 8-year-old Caucasian boy from eastern Morocco who was initially hospitalized for a hemorrhagic syndrome. Peripheral blood smear examination showed a significant number of blasts suggesting acute leukemia. Bone marrow was studied for morphology, cytochemistry, immunophenotyping, and cytogenetics. Flow cytometry analyses showed expression of CD19, CD22, CD10, CD34, and HLA-DR markers by leukemic blasts. The expression of CD79a, which was checked with two different monoclonal antibodies, confirms that this marker was severely decreased in this case. Cytogenetic study performed by fluorescence in situ hybridization revealed the presence of intrachromosomal amplification of chromosome 21, a cytogenetic abnormality that is specific for B acute lymphoblastic leukemia.

CONCLUSION

CD79a is one of the critical markers in the assignment of B acute lymphoblastic leukemia. In our case, we were lucky enough to be assisted by a few other markers of the B lineage that were positive in this case. Also, we mention the importance of proceeding to cytogenetic study, which in our case helped us to confirm the diagnosis made by flow cytometry by highlighting a cytogenetic abnormality that is specific to B acute lymphoblastic leukemia.

Effects of Highly-pure-enriched-cellulose Diet on Digestibility, Lipid Metabolism and Redox Status in Obese Offspring of Streptozotocin-Induced Diabetic Rats

The long-term nutritional efficacy of a highly-pure-enriched-cellulose (HPEC) diet and its effects on lipid metabolism and oxidant/antioxidant status were investigated in obese offspring of streptozotocin-induced diabetic rats. Diabetes in pregnant rats was induced by intraperitoneal injection of streptozotocin on day 5 of gestation. Control pregnant rats were injected with citrate buffer. At weaning offspring of diabetic and control rats were fed HPEC or control diet, they were housed individually in metabolic cage for 2 months to investigate the nutritional efficacy of the diets. Consumption of HPEC diet decrease weight gain and energy intake, increase fecal weight and reduce lipid and protein digestibility; however, these diet had no effect on protein utilization, and nitrogen balance remained positive which confirms that HPEC diet had no significant long-term nutritional risks. Indeed for obese offspring from diabetic rats, these diet associated with high satiety promote weight loss, and provide reasonable glycemic control, these diet also lower blood lipids concentration and correct the imbalance of oxidant/antioxidant system. HPEC diet had a protective effect against long-term metabolic abnormalities associated with macrosomia.

[Diagnostic difficulty for an acute hydrocephalus]

Tuberculosis disease, in its extra pulmonary form, remains a difficult diagnosis because of its atypical symptoms and evolution. We have observed a case of acute tuberculosis neuromeningitis, without being able to make a definite diagnosis prior to the patient's death because of the negativity of the initial bacteriological samples. We started the most probable appropriate treatment but in vain. This case allows us to challenge diagnostic methods and resulting treatments in emergency cases where tuberculosis is suspected. Moreover, it seems essential to do everything possible to find the bacterium when confronted with a patient with risk factors and clinical and radiological symptoms compatible with tubercular disease, before the disease becomes acute.

[Atypical hemolytic and uremic syndrome associated with von Willebrand factor-cleaving protease (ADAMTS 13) deficiency in children]

Hemolytic and uremic syndrome (HUS) is a classical form of thrombotic microangiopathies characterized by the association of hemolytic anemia with schizocytes, thrombocytopenia, and acute renal failure. Two forms of HUS have been described: the typical form that occurs after ingestion of a strain of bacteria, usually Escherichia coli types, which expresses verotoxin (also called shiga-like toxin), typically followed by bloody diarrhea, and atypical HUS, which is rare during childhood and can also be revealed by bloody diarrhea. We report a case of a 25-month-old infant who presented with hematuria and pallor after an episode of diarrhea. Biological tests revealed anemia, thrombocytopenia, and renal failure. The diagnosis of typical HUS was made, but the causal microorganism was not identified. Progression was favorable within 5 days of plasma transfusions. Two months later, the patient presented with the same symptoms and neurological impairment without any diarrhea. Von Willebrand factor-cleaving protease activity (ADAMTS 13) was low. Therefore, the diagnosis of atypical HUS by severe deficiency of ADAMTS 13 was suggested. The treatment was based on plasma transfusions resulting in remission. Atypical HUS associated with severe ADAMTS 13 deficiency rarely occurs in childhood. The prognosis, usually threatening, has been completely transformed thanks to a better understanding of the pathogenesis and to therapeutic progress.

Diagnosis and treatment of pulmonary arteriovenous malformations in hereditary hemorrhagic telangiectasia: An overview

Hereditary hemorrhagic telangiectasia (HHT) or Rendu-Osler-Weber disease is an autosomic dominant disorder, which is characterized by the development of multiple arteriovenous malformations in either the skin, mucous membranes, and/or visceral organs. Pulmonary arteriovenous malformations (PAVMs) may either rupture, and lead to life-threatening hemoptysis/hemothorax or be responsible for a right-to-left shunting leading to paradoxical embolism, causing stroke or cerebral abscess. PAVMs patients should systematically be screened as the spontaneous complication rate is high, by reaching almost 50%. Neurological complications rate is considerably higher in patients presenting with diffuse pulmonary involvement. PAVM diagnosis is mainly based upon transthoracic contrast echocardiography and CT scanner examination. The latter also allows the planification of treatments to adopt, which consists of percutaneous embolization, having replaced surgery in most of the cases. The anchor technique consists of percutaneous coil embolization of the afferent pulmonary arteries of the PAVM, by firstly placing a coil into a small afferent arterial branch closely upstream the PAVM. Enhanced contrast CT scanner is the key follow-up examination that depicts the PAVM enlargement, indicating the various mechanisms of PAVM reperfusion. When performed by experienced operators as the prime treatment, percutaneous embolization of PAVMs, is a safe, efficient and sustained therapy in the great majority of HHT patients.

Anti-tumor properties of blackseed (Nigella sativa L.) extracts

The objective of the present study was to evaluate the in vitro and in vivo anti-cancer effect of Nigella sativa L. seed extracts. The essential oil (IC50 = 0.6%, v/v) and ethyl acetate (IC50 = 0.75%) extracts were more cytotoxic against the P815 cell line than the butanol extract (IC50 = 2%). Similar results were obtained with the Vero cell line. Although all extracts had a comparable cytotoxic effect against the ICO1 cell line, with IC50 values ranging from 0.2 to 0.26% (v/v), tests on the BSR cell line revealed a high cytotoxic effect of the ethyl acetate extract (IC50 = 0.2%) compared to the essential oil (IC50 = 1.2%). These data show that the cytotoxicity of each extract depends on the tumor cell type. In vivo, using the DBA2/P815 (H2d) mouse model, our results clearly showed that the injection of the essential oil into the tumor site significantly inhibited solid tumor development. Indeed, on the 30th day of treatment, the tumor volume of the control animals was 2.5 +/- 0.6 cm(3), whereas the tumor volumes of the essential oil-treated animals were 0.22 +/- 0.1 and 0.16 +/- 0.1 cm(3) when the animals were injected with 30 microL (28.5 mg)/mouse and 50 microL (47.5 mg)/mouse per 48 h (six times), respectively. Interestingly, the administration of the essential oil into the tumor site inhibited the incidence of liver metastasis development and improved mouse survival.