Hematological Findings among COVID-19 Patients Attending King Khalid Hospital at Najran, Kingdom of Saudi Arabia

COVID-19 is a global pandemic viral infection that has affected millions worldwide. Limited data is available on the effect of COVID-19 on hematological parameters in Saudi Arabia. This study is aimed at examining the role of hematological parameters among COVID-19 patients admitted to King Khalid Hospital in Najran, Saudi Arabia. This is a retrospective, hospital-based study of 514 cases who were recruited during August to October 2020. 257 COVID-19 patients formed the study group, and a further 257 negative subjects formed the control group. Anemia was significantly elevated in positive subjects over controls (respectively, 64.2% and 35.8%), with patients 2.5 times more likely to be anemic (p < 0.01). Thrombocytopenia was higher in patients over controls (respectively, 62% and 38%), with patients ~1.7 times more likely to be thrombocytopenic (p < 0.01). Moreover, leukopenia was significantly higher in patients over controls (respectively, 71% and 29%), with positive subjects ~2.6 times more likely to be leukopenic. Our study results indicate that mild anemia associated with leukopenia may have diagnostic value for COVID-19. Careful assessment of hematological parameters, at baseline and throughout the disease path, will assist physicians in formulating personalized approaches to treatment and promptly offer intensive care to those in greater need.

COVID-19 associated symmetrical peripheral gangrene: A case series

BACKGROUND AND AIMS

The novel coronavirus disease (COVID-19) caused by SARS-CoV-2 has turned the world topsy-turvy since its onset in 2019. The thromboinflammatory complications of this disease are common in critically ill patients and associated with poor prognosis. Symmetrical peripheral gangrene (SPG) is characterized by symmetrical distal gangrene in absence of any large vessel occlusion or vasculitis and it is usually associated with critical illness. Our aim was to report the clinical profile and outcome of patients diagnosed with SPG associated with COVID-19. To the best of our knowledge, no such similar cases have been reported till date.

METHODS

In this case series, we have discussed the clinical presentation, laboratory parameters and outcome in a series of two patients of SPG associated with COVID-19 and also compared those findings. Due to paucity of data, we also reviewed the literature on this under-diagnosed and rarely reported condition and association.

RESULTS

Two consecutive patients (both males, age range: 37-42 years, mean: 39.5 years) were admitted with the diagnosis of COVID-19 associated SPG. Both patients had clinical and laboratory evidence of disseminated intravascular coagulation (DIC). Leucopenia was noted in both patients. Despite vigorous therapy, both patients succumbed to their illness within a fortnight of admission.

CONCLUSION

SPG in the background of COVID-19 portends a fatal outcome. Physicians should be aware of its grim prognosis.

Magnitude and associated factors of peripheral cytopenia among HIV-infected children attending at University of Gondar Specialized Referral Hospital, Northwest Ethiopia

BACKGROUND

Isolated or multi lineage cytopenia are the most common clinicopathological features and independently associated with increased risk of disease progression and death among human immunodeficiency virus infected children. In the study area, there is scarcity of data about the magnitude of various cytopenia.

OBJECTIVES

Aimed to determine the magnitude and associated factors of peripheral cytopenia among HIV infected children at the University of Gondar Specialized Referral Hospital ART clinic, Northwest Ethiopia.

METHODS

Institutional based cross-sectional study was conducted on 255 HIV infected children from January- April 2020. None probable convenient sampling technique was used to select the study participant. Socio demographic data were collected by pre tested structured questionnaire via face-to-face interview and their medical data were obtained from their follow-up medical records. Moreover, blood specimens were collected and examined for complete blood count, viral load and blood film, whereas stool specimens were collected and examined for intestinal parasites. Bi-variable and multi-variable logistic regression models were fitted to identify associated factors of cytopenia. P-Value <0.05 was considered as statistically significant.

RESULT

The overall magnitude of peripheral cytopenia was 38.9%. Anemia, leukopenia, lymphopenia, thrombocytopenia and bi-cytopenia were 21.2%, 12.2%, 11%, 1.6% and 3.9% respectively. Being in the age group of 2-10 years (AOR = 5.38, 95%CI 2.33-12.46), AZT based regimen (AOR = 5.44, 95%CI: 2.24-13.21), no eating green vegetables (AOR = 2.49, 95% CI: 1.26-4.92) and having plasma viral load >1000 copies /ml (AOR = 5.38, 95%CI: 2.22-13.03) showed significant association with anemia.

CONCLUSION

Anemia was the predominant peripheral cytopenia among HIV infected children in this study. It was strongly associated with AZT based drug type, age below 10 years and high viral load. Critical stress should be given for early investigation and management of cytopenia in addition to the use of alternative drug which leads to higher viral suppression and lower risk of toxicity issue.

Potential benefits and risks of omega-3 fatty acids supplementation to patients with COVID-19

Studies have shown that infection, excessive coagulation, cytokine storm, leukopenia, lymphopenia, hypoxemia and oxidative stress have also been observed in critically ill Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) patients in addition to the onset symptoms. There are still no approved drugs or vaccines. Dietary supplements could possibly improve the patient's recovery. Omega-3 fatty acids, specifically eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), present an anti-inflammatory effect that could ameliorate some patients need for intensive care unit (ICU) admission. EPA and DHA replace arachidonic acid (ARA) in the phospholipid membranes. When oxidized by enzymes, EPA and DHA contribute to the synthesis of less inflammatory eicosanoids and specialized pro-resolving lipid mediators (SPMs), such as resolvins, maresins and protectins. This reduces inflammation. In contrast, some studies have reported that EPA and DHA can make cell membranes more susceptible to non-enzymatic oxidation mediated by reactive oxygen species, leading to the formation of potentially toxic oxidation products and increasing the oxidative stress. Although the inflammatory resolution improved by EPA and DHA could contribute to the recovery of patients infected with SARS-CoV-2, Omega-3 fatty acids supplementation cannot be recommended before randomized and controlled trials are carried out.

CT Manifestations and Clinical Characteristics of 1115 Patients with Coronavirus Disease 2019 (COVID-19): A Systematic Review and Meta-analysis

RATIONALE AND OBJECTIVES

We aimed to assess the prevalence of significant computed tomographic(CT) manifestations and describe some notable features based on chest CT images, as well as the main clinical features of patients with coronavirus disease 2019(COVID-19).

MATERIALS AND METHODS

A systematic literature search of PubMed, EMBASE, the Cochrane Library, and Web of Science was performed to identify studies assessing CT features, clinical, and laboratory results of COVID-19 patients. A single-arm meta-analysis was conducted to obtain the pooled prevalence and 95% confidence interval (95% CI).

RESULTS

A total of 14 articles (including 1115 patients) based on chest CT images were retrieved. In the lesion patterns on chest CTs, we found that pure ground-glass opacities (GGO) (69%, 95% CI 58-80%), consolidation (47%, 35-60%) and "air bronchogram sign" (46%, 25-66%) were more common than the atypical lesion of "crazy-paving pattern" (15%, 8-22%). With regard to disease extent and involvement, 70% (95% CI 46-95%) of cases showed a location preference for the right lower lobe, 65% (58-73%) of patients presented with ≥3 lobes involvement, and meanwhile, 42% (32-53%) of patients had involvement of all five lobes, while 67% (55-78%) of patients showed a predominant peripheral distribution. An understanding of some important CT features might be helpful for medical surveillance and management. In terms of clinical features, muscle soreness (21%, 95% CI 15-26%) and diarrhea (7%, 4-10%) were minor symptoms compared to fever (80%, 74-87%) and cough (53%, 33-72%).

CONCLUSION

Chest CT manifestations in patients with COVID-19, as well as its main clinical characteristics, might be helpful in disease evolution and management.

The evolutionary history and spatiotemporal dynamics of the fever, thrombocytopenia and leukocytopenia syndrome virus (FTLSV) in China

Background

In 2007, a novel bunyavirus was found in Henan Province, China and named fever, thrombocytopenia and leukocytopenia syndrome virus (FTLSV); since then, FTLSV has been found in ticks and animals in many Chinese provinces. Human-to-human transmission has been documented, indicating that FTLSV should be considered a potential public health threat. Determining the historical spread of FTLSV could help curtail its spread and prevent future movement of this virus.

Method/Principal Findings

To examine the pattern of FTLSV evolution and the origin of outbreak strains, as well to examine the rate of evolution, the genome of 12 FTLSV strains were sequenced and a phylogenetic and Bayesian phylogeographic analysis of all available FTLSV sequences in China were performed. Analysis based on the FTLSV L segment suggests that the virus likely originated somewhere in Huaiyangshan circa 1790 (95% highest probability density interval: 1756–1817) and began spreading around 1806 (95% highest probability density interval: 1773–1834). Analysis also indicates that when FTLSV arrived in Jiangsu province from Huaiyangshan, Jiangsu Province became another source for the spread of the disease. Bayesian factor test analysis identified three major transmission routes: Huaiyangshan to Jiangsu, Jiangsu to Liaoning, and Jiangsu to Shandong. The speed of FTLSV movement has increased in recent decades, likely facilitated by modern human activity and ecosystem changes. In addition, evidence of RNA segment reassortment was found in FTLSV; purifying selection appears to have been the dominant force in the evolution of this virus.

Conclusion

Results presented in the manuscript suggest that the Huaiyangshan area is likely be the origin of FTLSV in China and identified probable viral migration routes. These results provide new insights into the origin and spread of FTLSV in China, and provide a foundation for future virological surveillance and control.

FTLSV is novel bunyavirus belonging to genus Phlebovirus and was first found in Huaiyangshan area. The epidemiology and pathogenesis of FTLSV remain poorly understood. This lack of information underscores the importance of analyzing the movement and genetic history of FTLSV in China. Recent advances in Bayesian coalescent phylogenetic analyses have resulted in more sophisticated methods being available for determining the relative age of emerging pathogens. In this study, a phylogenetic and Bayesian phylogeographic analysis was performed for FTLSV whole genomic sequences isolated from China. Results identified the Huaiyangshan area as the most probable origin of FTLSV and suggested migrating routes of the virus. These results offer the first description of the movement and history of FTLSV in China. RNA segment reassortment was found in FTLSV; purifying selection appears to have been the dominant force driving the evolution of this virus. The results of this study could be used to facilitate the development of new strategies for controlling FTLSV.

Severe fever with thrombocytopenia syndrome, Shandong Province, China, 2011

Supportive therapy is recommended before laboratory confirmation of this disease.

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease in China. The incidence and clinical and laboratory characteristics of SFTS are not clearly defined. During May 22–October 2, 2011, a total of 24 patients with fever, thrombocytopenia, and leukopenia were clinically diagnosed as having SFTS in Yiyuan County, Shandong Province, China. We conducted laboratory tests for these SFTS patients. SFTS virus (SFTSV) infection was confirmed in 22 patients by using reverse transcription PCR and ELISA by acute-phase and convalescent-phase serum samples. Clinical and laboratory manifestations included fever (100%), gastrointestinal symptoms (91%), myalgia (55%), chills (41%), thrombocytopenia (100%), and leukopenia (95%).

Haematological abnormalities associated with paediatric HIV/AIDS in Lagos

INTRODUCTION

In HIV-1-infected children, haematological disturbances include bone marrow abnormalities and peripheral cytopenias. All three major cell lineages can be depressed.

METHODS

A cross-sectional study of baseline haematological parameters was undertaken in 68 children with confirmed HIV infection. In all cases, a complete blood count was done and some had CD4+ counts and HIV RNA PCR. The CD4+ count was analysed by the Coulter manual latex particle monoclonal antibody method and HIV RNA PCR by Roche Amplicor Monitor, version 1.5.

RESULTS

Anaemia (< 100 g/L) was present in 77.9%, severe (< 60 g/L) in 5.9%, moderate (60-70 g/L) in 32.3% and mild (80-99 g/L) in 39.7%. The mean haemoglobin concentration decreased as disease progressed (p < 0.05); 6% had leucopenia, 17.5% had neutropenia and 2.5% (one case) had thrombocytopenia; also, the four (6%) subjects with leucopenia were in clinical stages B and C. Neutropenia, lymphocytopenia and thrombocytopenia were seen more in clinical stages B and C, though this relationship was not statistically significant.

CONCLUSION

Both the erythroid and other cells lines are affected by HIV/AIDS and other associated factors. Anaemia is the most common haematological abnormality. The severity of peripheral cytopenias is related to the disease burden.

Measles immune suppression: lessons from the macaque model

Measles remains a significant childhood disease, and is associated with a transient immune suppression. Paradoxically, measles virus (MV) infection also induces robust MV-specific immune responses. Current hypotheses for the mechanism underlying measles immune suppression focus on functional impairment of lymphocytes or antigen-presenting cells, caused by infection with or exposure to MV. We have generated stable recombinant MVs that express enhanced green fluorescent protein, and remain virulent in non-human primates. By performing a comprehensive study of virological, immunological, hematological and histopathological observations made in animals euthanized at different time points after MV infection, we developed a model explaining measles immune suppression which fits with the "measles paradox". Here we show that MV preferentially infects CD45RA(-) memory T-lymphocytes and follicular B-lymphocytes, resulting in high infection levels in these populations. After the peak of viremia MV-infected lymphocytes were cleared within days, followed by immune activation and lymph node enlargement. During this period tuberculin-specific T-lymphocyte responses disappeared, whilst strong MV-specific T-lymphocyte responses emerged. Histopathological analysis of lymphoid tissues showed lymphocyte depletion in the B- and T-cell areas in the absence of apoptotic cells, paralleled by infiltration of T-lymphocytes into B-cell follicles and reappearance of proliferating cells. Our findings indicate an immune-mediated clearance of MV-infected CD45RA(-) memory T-lymphocytes and follicular B-lymphocytes, which causes temporary immunological amnesia. The rapid oligoclonal expansion of MV-specific lymphocytes and bystander cells masks this depletion, explaining the short duration of measles lymphopenia yet long duration of immune suppression.

Clinical features of 167 children with the novel influenza A (H1N1) virus infection in Xi'an, China

Since its first recognition, the 2009 pandemic influenza A (H1N1) virus rapidly spread worldwide. We observed the clinical characteristics of 167 hospitalized patients who were confirmed by testing pharyngeal or nasopharyngeal swabs with the use of a real-time reverse-transcriptase polymerase chain reaction (RT-PCR) assay. The mean age of the 167 hospitalized patients was 4.1 years, and 58.7% were male. The most common symptoms and signs were fever (91.6%), cough (82.6%), pharyngeal congestion (95.2%), and swollen tonsils (34.1%). The major complications were bronchitis (19.2%), bronchial pneumonia (10.8%), neutropenia (49.7%), and leukopenia (38.9%). The duration of hospitalization, fever and the course of disease in the patients who were treated with oseltamivir were shorter than in those who were treated with ribavirin. All of the patients fully recuperated from the 2009 epidemic influenza A (H1N1) infection with one exception.

Changing haematological parameters in dengue viral infections

BACKGROUND

Dengue Fever is the most common arboviral disease in the world, and presents cyclically in tropical and subtropical regions of the world. The four serotypes of dengue virus, 1, 2, 3, and 4, form an antigenic subgroup of the flaviviruses (Group B arboviruses). Transmission to humans of any of these serotypes initiates a spectrum of host responses, from in apparent to severe and sometimes lethal infections. Complete Blood count (CBC) is an important part of the diagnostic workup of patients. Comparison of various finding in CBC including peripheral smear can help the physician in better management of the patient.

MATERIAL AND METHODS

This cross sectional study was carried out on a series of suspected patients of Dengue viral infection reporting in Ittefaq Hospital (Trust). All were investigated for serological markers of acute infection.

RESULTS

Out of 341 acute cases 166 (48.7%) were confirmed by IgM against Dengue virus. IgG anti-dengue was used on 200 suspected re-infected patients. Seventy-one (39.5%) were positive and 118 (59%) were negative. Among 245 confirmed dengue fever patients 43 (17.6%) were considered having dengue hemorrhagic fever on the basis of lab and clinical findings. Raised haematocrit, Leukopenia with relative Lymphocytosis and presence atypical lymphocytes along with plasmacytoid cells was consistent finding at presentation in both the patterns of disease, i.e., Dengue Haemorrhagic fever (DHF) and Dengue fever (DF).

CONCLUSION

Changes in relative percentage of cells appear with improvement in the symptoms and recovery from the disease. These findings indicate that in the course of the disease, there are major shifts within cellular component of blood.

Utility of the tourniquet test and the white blood cell count to differentiate dengue among acute febrile illnesses in the emergency room

Dengue often presents with non-specific clinical signs, and given the current paucity of accurate, rapid diagnostic laboratory tests, identifying easily obtainable bedside markers of dengue remains a priority. Previous studies in febrile Asian children have suggested that the combination of a positive tourniquet test (TT) and leucopenia can distinguish dengue from other febrile illnesses, but little data exists on the usefulness of these tests in adults or in the Americas. We evaluated the diagnostic accuracy of the TT and leucopenia (white blood cell count <5000/mm³) in identifying dengue as part of an acute febrile illness (AFI) surveillance study conducted in the Emergency Department of Saint Luke's Hospital in Ponce, Puerto Rico. From September to December 2009, 284 patients presenting to the ED with fever for 2–7 days and no identified source were enrolled. Participants were tested for influenza, dengue, leptospirosis and enteroviruses. Thirty-three (12%) patients were confirmed as having dengue; 2 had dengue co-infection with influenza and leptospirosis, respectively. An infectious etiology was determined for 141 others (136 influenza, 3 enterovirus, 2 urinary tract infections), and 110 patients had no infectious etiology identified. Fifty-two percent of laboratory-positive dengue cases had a positive TT versus 18% of patients without dengue (P<0.001), 87% of dengue cases compared to 28% of non-dengue cases had leucopenia (P<0.001). The presence of either a positive TT or leucopenia correctly identified 94% of dengue patients. The specificity and positive predictive values of these tests was significantly higher in the subset of patients without pandemic influenza A H1N1, suggesting improved discriminatory performance of these tests in the absence of concurrent dengue and influenza outbreaks. However, even during simultaneous AFI outbreaks, the absence of leucopenia combined with a negative tourniquet test may be useful to rule out dengue.

In the Americas, the incidence and severity of dengue cases has increased dramatically in the past 30 years. Early diagnosis and initiation of appropriate therapy can substantially reduce dengue morbidity and mortality. However the absence of a point-of-care diagnostic test and the non-specific clinical signs and symptoms in early disease make differentiating dengue from other acute febrile illnesses challenging. Identifying dengue during an outbreak of another disease is especially difficult. The combination of a simple bedside test, the tourniquet test (TT), and a readily available laboratory test, the white blood cell count, has been reported to be a useful triage tool for identifying children with dengue in Asia, but little information exists on the performance of these tests in the Americas or among adults. We evaluated the utility of these tests in the setting of a concurrent influenza epidemic in Puerto Rico in 2009. A positive TT or leucopenia (white blood cell count <5000) was present in 94% of patients with laboratory proven dengue. Patients without either of these findings rarely had dengue. Our study indicates that a combination of two rapid, widely available tests can assist clinicians in distinguishing dengue from other illnesses with similar signs and symptoms.

Natural leukocyte interferon alpha (Alfaferone) combined with ribavirin in the treatment of patients with HCV-related cirrhosis: our experience

BACKGROUND

The aim of the study was to evaluate the efficacy and safety of combined treatment with natural leukocyte interferon alpha (Alfaferone) plus ribavirin in patients with HCV-related cirrhosis.

PATIENTS AND METHODS

Twenty-three patients (15 women, 8 men) aged 17-68 years hospitalized in 2005-2008 were included in the study. Seventeen patients who qualified for treatment were Child-Pugh class A patients and 6 others were class B. Seventeen patients had genotype 1b and 6 genotype 3a infection. Thirteen patients were naïve, retherapy concerned 8 patients, and in two cases the continuation of treatment had been stopped because of adverse events following the use of pegylated interferons. The treatment was continued for 48 weeks regardless of HCV genotype. Normalized AlAT activity (<40 U/l) was the measure of biochemical efficacy of the treatment, while virological efficacy was reflected by an undetectable viral load in plasma. Both measurements were conducted immediately after the end of treatment (EOT) and after a 6-month follow-up period (SVR). Therapeutic safety was evaluated by the monitoring of the adverse events of the treatment.

RESULTS

Abnormal AlAT levels prior to treatment were detected in 20/23 patients. During therapy normalized levels were achieved in 50% of them, and after 6 months they were sustained in 9/20. EOT was achieved in 6/19 patients and SVR in 3 patients. Mild psychiatric disorders were the most frequently detected adverse events (12 patients). Thrombocytopenia and leucopenia existing prior to treatment did not intensify during the treatment. Severe adverse events caused by the drug resulted in the discontinuation of treatment in three patients (urinary tract infections, depression, myasthenia gravis), of whom two patients were Child-Pugh class A and one was class B. In one patient treatment was discontinued because of HCC.

CONCLUSION

Natural leukocyte interferon alpha is well tolerated by patients with HCV-related cirrhosis and coexisting thrombocytopenia and leucopenia.

[Leucopenia in children]

Decreased leukocyte values in children are usually due to the decrease in the number of neutrophilic granulocytes. This is usually a transient phenomenon associated with viral infections. In infancy and early childhood, immune mediated neutropenias are possible causes of prolonged leukopenia. Causes of rare leukopenias are numerous, including underlying diseases such as congenital myelopathy, a syndrome or malignant hematological disease. The risk of infection associated with neutropenia is increased especially in patients with a production defect of the bone marrow as the underlying cause.

[Prolonged bone marrow aplasia in patients with acute leukemia after chemotherapy]

AIM

To analyze the causes of prolonged hematopoietic tissue aplasias in patients with acute leukemias (AL) after chemotherapy courses.

MATERIALS AND METHODS

Data on 7 patients with acute myeloid leukemia, followed up at the Hematology Departments, Hematology Research Center, Russian Academy of Medical Sciences, over the period 2003 to 2007, who had developed deep bone marrow aplasia (BMA) inadequate to cytostatic drug exposure during chemotherapy, were analyzed. The authors compared in all the patients the values of peripheral blood and bone marrow (BM) puncture specimens and the results of blood tests using the polymerase chain reaction at different AL development stages with the results of an immunohistochemical study using the markers of viruses of hepatitis C and B, a herpes group (EBV, CMV, HSV-1, HSV-2) and parvovirus B19.

RESULTS

The marker of hepatitis C was detected in 6 of the 7 patients with prolonged BMA; 3 of these 6 patients showed a simultaneous infection with hepatitis B. Six of the 7 patients were found to have concomitant BM lesion with various herpes group viruses. Two patients had a resistant form of AL.

CONCLUSION

Hepatitis C virus infection in patients and the resistant form of the disease were the principal causes of the development of BMA inadequate to cytostatic drug exposure. Affliction of abundant bone marrow cells with herpes group viruses was not a direct cause, but might substantially aggravate BMA.

Experimental infection of dogs with a novel strain of canine coronavirus causing systemic disease and lymphopenia

A pantropic canine coronavirus (CCoV) strain (CB/05) has been recently associated to a fatal outbreak of systemic disease in young dogs. We report the clinical, virological and serological findings in dogs experimentally infected with strain CB/05. The dogs, three 2.5-month-old and two 6-month-old pups, were successfully infected, shedding viral RNA with their faeces for the entire observation period (21 days) and displaying systemic clinical signs resembling those observed during the course of natural infection. Leucopenia (acute lymphopenia) occurred in all infected dogs, with values dropping below 60% of the initial counts. Considering the severity of the CB/05-induced disease, two of the youngest pups were euthanized for ethical reasons at days 8–9 postinfection, whereas the other pups underwent a slow but progressive improvement of their clinical status with complete recovery. At postmortem examination, remarkable lesions were observed in the internal organs of the euthanized pups, that tested positive for CCoV by real-time RT-PCR and virus isolation on cell cultures. All pups seroconverted for CCoV, as shown by the high optical density values and antibody titres detected by ELISA and virusneutralisation tests, respectively. The present study confirms that strain CB/05 is highly pathogenic for dogs, being able to induce a severe disease (and in some cases the death) even in experimental conditions.

Correlation Between Body Mass Index and Leucopenia After Administration of Valganciclovir for Cytomegalovirus Infection in Chinese Cardiac Recipients

BACKGROUND

Valganciclovir (VGC) has recently been proved efficacious for the prophylaxis and treatment of cytomegalovirus (CMV) infection in transplant recipients. Leucopenia is a troublesome complication of VGC but the possible risk factors are unknown.

METHODS AND RESULTS

Once a cardiac recipient's quantitative real-time CMV-polymerase chain reaction result showed positive, VGC was administered for 3 months. The 61 cardiac recipients enrolled in this study were divided into 2 groups: non-leucopenia group (n=29) and leucopenia group (n=32). The white blood cell (WBC) counts in the leucopenia group dropped approximately 55.6% in the first month after VGC therapy (pre-VGC WBC count: 5,544 cells/mm(3) vs post-VGC WBC count: 2,460 cells/mm(3), p<0.0001). The most significant difference between the 2 groups was body mass index (BMI, 23.04 vs 25.84, p=0.008), which was the impact factor of VGC-induced leucopenia.

CONCLUSION

Severe leucopenia may develop after VGC therapy in Chinese cardiac recipients, especially those with lower BMI.

Peripheral Blood Leukocyte Counts in Cytomegalovirus Infected Heart Transplant Patients: Impact of Acute Disease Versus Subclinical Infection

BACKGROUND

Cytomegalovirus (CMV)-associated leucopenia in heart transplant patients is poorly characterized.

METHODS

We conducted a retrospective analysis of timing, degree, and type of leukopenia in four groups of patients: cases (n=20); controls (n=20); subclinical early infection (n=21), and subclinical late infection (n=22). In the cases, white blood cells (WBC) count at diagnosis was compared to prediagnosis; and cases were compared to controls. Subclinical cases (early and late) were identified by measurement of CMV DNA in peripheral blood mononucleocytes, and WBC was compared to those of the cases and controls.

RESULTS

First, in human heart transplant recipients the total leukocyte count decreased prior to the time of diagnosis of CMV disease: cases: 5.4+/-2.1 x 10/microL vs. 3.7+/-2.1x10/muL (P<0.01); subclinical early: 8.1+/-4.1 x 10/microL vs. 6.9+/-1.6 x 10/microL (P<0.01). Second, the leukocyte populations most reduced during CMV disease are the neutrophils: 4.4 x 10/microL (78%) to 2.5 x 10/microL (69%) (P<0.05), and monocytes 0.6 x 10/microL (11%) to 0.3 x 10/microL (7.5%) (P<0.05). Third, the reduction in leukocyte count that occurs during CMV disease appears to be independent of immunosuppressive therapy (using cyclosporine A, mycophenolate mofetil, or azathioprine and prednisone). Finally, subclinical CMV infection in stable long-term heart transplant patients without disease is unassociated with a reduction in the leukocyte count.

CONCLUSIONS

Aside from implications for early diagnosis, CMV-associated decrease in monocytes is important because viral infections like Epstein-Barr virus cause monocytosis. The absence of leucopenia in subclinical late infections is a new important finding.

A role for virus promoters in determining the pathogenesis of Rinderpest virus in cattle

Rinderpest virus (RPV) is a morbillivirus that causes cattle plague, a disease of large ruminants. The viral genome is flanked at the 3′ and 5′ genome termini by the genome promoter (GP) and antigenome promoter (AGP), respectively. These promoters play essential roles in directing replication and transcription as well as RNA encapsidation and packaging. It has previously been shown that individual changes to the GP of RPV greatly affect promoter activity in a minigenome assay and it was therefore proposed that individual nucleotide changes in the GP and AGP might also have significant effects on the ability of the virus to replicate and cause disease in cattle. The Plowright vaccine strain of RPV has been derived by tissue-culture passage from the virulent Kabete ‘O’ isolate (KO) and is highly attenuated for all ruminant species in which it has been used. Here, it was shown that swapping the GP and the first 76 nt of the AGP between virulent and avirulent strains affected disease progression. In particular, it was shown that flanking the virulent strain with the vaccine GP and AGP sequences, while not appreciably affecting virus growth in vitro, led to attenuation in vivo. The reverse was not true, since the KO promoters did not alter the vaccine's attenuated nature. The GP/AGP therefore play a role in attenuation, but are not the only determinants of attenuation in this vaccine.

Enteroviruses and sudden deafness

A young, healthy man presented with sudden severe sensorineural hearing loss and tinnitus. The results of the workup and neuroimaging were normal, as were the auditory brain stem responses. Methylprednisolone pulse therapy was associated with significant hearing improvement within 10 days. A history of a short self-limited febrile illness preceding admission (with headache, photophobia, myalgia and fatigue), a raised serum C-reactive protein level and transient leukopenia suggested an infectious cause. Lumbar puncture revealed a mononuclear pleocytosis of the cerebrospinal fluid, with negative cultures but positive polymerase chain reaction test results for enterovirus, which was later cultured from the patient's stool. The patient's wife and baby had had a similar febrile illness without hearing loss 10 days earlier, and an outbreak of enterovirus meningitis was identified in the area, which was associated with familial clustering and echovirus serotype 4 infection. The varied causes of sudden sensorineural hearing loss, which should include enterovirus, are reviewed here.

Effect of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on leukocyte count and survival rate of dogs with parvoviral enteritis

Dogs with clinical signs consistent with parvoviral enteritis and leukopenia (total leukocyte count < 5.0 x 10(9) l(-1)) were included in this randomised double-blind study (treatment group: n = 22; control group: n = 21). The dogs in the treatment group received a subcutaneous daily injection of 10 microg kg(-1) of recombinant human granulocyte colony-stimulating factor (rhG-CSF) for 5 days. Clinical and blood investigations were performed prior to the first injection, daily during the treatment period and on the day after treatment ended, and then once more, 26 days after the first injection. During the study, no significant differences were found between the two groups with respect to survival rate (treatment group: 68 per cent; control group: 71 per cent, P > 0 4, Fisher-Test) and other clinical findings. Similarly the total leukocyte count, neutrophil count and other haematologic and biochemical parameters did not differ significantly between the groups, based on differences from initial values (P > 0 05). Consequently, the use of rhG-CSF in the treatment of dogs with parvoviral enteritis cannot be recommended.

Detection of active hepatitis C virus and hepatitis G virus/GB virus C replication in bone marrow in human subjects

We have analyzed the presence of hepatitis C virus (HCV) and hepatitis G virus (HGV) sequences in bone marrow and serum samples from 48 patients of a hematologic outpatient clinic. HCV RNA was detected in 18 (38%) and 15 (31%) and HGV RNA was detected in 6 (13%) and 9 (19%) of serum and bone marrow samples, respectively. In 3 patients, HGV RNA was detectable in bone marrow but not in the serum; 2 of these patients were negative for the presence of specific antibodies. Using a highly strand-specific Tth-based reverse transcriptase-polymerase chain reaction (RT-PCR), the presence of HCV RNA and HGV RNA negative strand was demonstrated in 4 and 5 bone marrow samples, respectively. Our study shows that HCV and HGV can replicate in bone marrow; in the case of HGV, analysis of serum may underestimate the true prevalence of infection. (Blood. 2000;95:3986-3989)

Cytopenia and past human parvovirus B19 infection in patients with primary Sjögren's syndrome

OBJECTIVES

To determine the clinical significance of human parvovirus B19 infection in patients with primary Sjögren's syndrome (SS) and to investigate the immunologic and hematologic features related to B19 infection.

METHODS

We included 80 consecutive patients with primary SS (74 women and 6 men), with a mean age of 62 years (range, 24 to 87 years) that were seen in our Unit. All patients fulfilled the European Community criteria for SS. As controls, we included 140 consecutive sera samples analyzed for B19 antibodies in our Microbiology Department and obtained from adult inpatients and outpatients of our Hospital. Serum from all patients and controls was tested for antibodies to B19 by enzyme-linked immunosorbent assay (ELISA). Additionally, the presence of B19 DNA in serum and in circulating leukocytes was investigated by nested polymerase chain reaction (PCR).

RESULTS

Serological evidence of past B19 infection (positive IgG antibodies without IgM antibodies) was present in 28 (35%) patients with primary SS. None of these patients showed evidence for B19 viremia, and B19 virus DNA was not detected in the circulating leukocytes of IgG-B19(+) patients. Positivity for IgM antibodies to B19 was not detected in any patient. When compared with patients without evidence of past B19 infection, those with primary SS and past B19 infection showed a higher prevalence of cytopenia (57% v 15%; P < .001), and, specifically, of leukopenia (36% v 4%; P < .001). Additionally, when compared with controls positive for IgG-B19, SS patients with these antibodies had a higher prevalence of cytopenia (57% v 13%; P < .001), leukopenia (36% v 3%; P < .001) and thrombocytopenia (21% v 0%; P = .003).

CONCLUSIONS

Serological evidence of past B19 infection is associated with the presence of cytopenia in our patients with primary SS. A possible relationship between B19 infection and the presence of cytopenia in primary SS may occur in some patients immunologically or genetically predisposed.

Strong alpha beta and gamma delta TCR response in a patient with disseminated Mycobacterium avium infection and lack of NK cells and monocytopenia

Infection with atypical mycobacteria occurs mainly in patients with a compromised cellular immune system, in particular in those with a defective T cell or monocyte function. Here we analyzed the specific immune response of an adolescent HIV-negative patient with disseminated mycobacterium avium infection and fatal varizella zoster virus infection. The patient presented with dysplastic hematopoesis of all cell lineage's and a bicytopenia of erythrocytes and leukocytes, but a hematological malignancy could not be found. We found a peripheral lymphopenia and monocytopenia, as well as a lack of NK-cells and B-cells. Lymphocytes consisted of 95% T cells, which contained up to 40% of TCR gammadelta+CD4-CD8-T-cells (mainly TCR gamma9delta2), few monocytes and B-cells. Approximately 50% of CD3+ T-cells showed a CD57+ NK-like phenotype. Functional analysis of PBMC revealed a good antigen-specific T cell function if antigen-presenting cells were supplemented from a HLA-matched donor. Moreover, a strong M. avium specific cytotoxicity mediated by TCR alphabeta+T-cells could be found in vitro and even ex vivo. In contrast, NK-killing was absent. No evidence for a defect in IL-12 or IFN-gamma production and signaling were found. The data indicate that a strong alphabeta and gammadelta T cell immunity tries to compensate for a deficient monocyte and NK cell function in this patient.

Comparison of the pathogenesis of acute equine herpesvirus 1 (EHV-1) infection in the horse and the mouse model: a review

The mouse models of the respiratory and abortion forms of equine herpesvirus 1 (EHV-1) infection have been used to investigate the vaccine potential of various EHV-1 immunogens, the effect of antiviral agents on EHV-1 infection and the pathogenicity of EHV-1 strain variants and deletion or insertional mutants. This review examines the similarities and differences in the pathogenesis of primary EHV-1 infection in the natural host, the horse, and in the mouse by comparing tissue tropism, clinical signs of infection, the effects of EHV-1 on pregnancy, haematological changes following infection, viral clearance, histopathology and latency. The evidence suggests that the mouse model provides a valid method for investigation of virological and histopathological aspects of EHV-1-induced disease in the horse. However, the extent to which useful and valid comparisons and extrapolations can be made of immunological parameters from mouse to horse is yet to be determined.

Clinical and laboratory findings in immunocompetent patients with persistent parvovirus B19 DNA in bone marrow

The clinical relevance of parvovirus B19 DNA persistence in bone marrow was examined in 10 immunocompetent individuals undergoing examinations for unexplained fever, arthralgia or chronic leukopenia. Common causes of these symptoms had been ruled out and bone marrow aspiration was indicated at this stage of investigation. In addition to morphological analysis of the bone marrow, a test for B19 DNA was performed with 2 nested PCRs. Five of these 10 selected patients had detectable B19 DNA in their bone marrow, whereas no viraemia was observed. Additional bone marrow samples were collected at least 6 months after the first sample from the B19 DNA-positive patients, of whom 3 were found to be still positive. Indeed, 2 of the patients have been positive for more than 5 y of follow-up. Sera from all patients with persistent B19 DNA in bone marrow could neutralize the virus. One patient responded to treatment with immunoglobulin but later relapsed. No other cause of the symptoms was found, despite extensive investigations, and at least some of the prolonged disease manifestations may be due to parvovirus B19.

Asymptomatic hepatitis G virus infection in blood donors

BACKGROUND

Hepatitis G virus (HGV) has been reported in patients with fulminant hepatitis and aplastic anemia, but HGV RNA has also been found in healthy individuals. The possible associations of HGV with liver function and hematologic abnormalities in asymptomatic blood donors were investigated.

STUDY DESIGN AND METHODS

Serum HGV RNA was determined in 200 repeat donors (Group A), 44 subjects with elevated alanine aminotransferase (Group B), and 54 hepatitis C virus carriers (Group C). Liver histology was evaluated in Group C by using the histologic activity index.

RESULTS

HGV RNA was detected in three subjects of Group A (1.5%; 95% CI: 0.3-4.3), two of Group B (4.5%; 95% CI: 0.6-15.5%), and six of Group C (11.1%; 95% CI: 4.2-22.6). The prevalence of leukopenia and elevated gamma-glutamyl transpeptidase was higher in the 11 viremic donors than in 88 nonviremic subjects (36% vs. 2.3%, and 55% vs. 22%, respectively; p < 0.05), matched for clinical and demographic characteristics. The mean histologic activity index score +/- standard error was 4 +/- 0.7 in the HGV RNA-positive donors and 3.4 +/- 0.3 in the HGV RNA-negative donors.

CONCLUSION

HGV is endemic in Italian blood donors, although it has a limited role in causing liver damage. Further studies are needed to clarify its role in inducing transfusion-associated disease in myelosuppression.

Hepatitis C virus-induced leuko-thrombocytopenia and haemolysis

Hepatitis C virus (HCV) has been recognized as the cause of thrombocytopenia occurring in patients with chronic hepatitis C, possibly through autoimmune mechanisms. A patient is described with B cell chronic lymphocytic leukaemia, presenting with a marked leuko-thrombocytopenia and an associated mild haemolysis secondary to HCV infection, in the absence of clinical and biochemical signs of hepatitis. Anti-HCV antibodies were detected in the serum both by ELISA and RIBA but not 2 months before the onset of cytopenia. The presence of HCV RNA was documented both in the peripheral blood mononuclear cells and in the bone marrow by reverse transcriptase polymerase chain reaction of the 5' untranslated region of the viral genome. Of interest, HCV RNA was also found in the serum, showing that viraemia was associated with the presence of circulating anti-HCV antibodies. HCV genotyping, performed by PCR amplification of the core region, revealed the presence of an unclassifiable genotype. The hypothetical mechanisms leading to HCV-induced cytopenia in this patient are briefly discussed. Treatment with corticosteroids was effective in controlling blood cell counts, without increasing viraemia and deterioration of liver disease. HCV infection should be considered in the differential diagnosis of possible causes of cytopenia, mainly in immunosuppressed patients, even in absence of clinical and biochemical signs of hepatitis.

Mechanisms of dengue virus-induced bone marrow suppression

Infection with many flaviviruses is associated with transient suppression of haematopoiesis. Of the flaviviruses of man, none are more accessible to clinical and laboratory study than dengue. Consequently, the clinical syndrome of dengue-associated bone marrow suppression has been well documented. A review of experimental dengue infections of volunteers and histopathological studies of bone marrow from patients with severe dengue virus infection suggests that marrow suppression evolves rapidly through several phases: (1) onset of marrow suppression within 3-4 days of infection; (2) onset of host inflammatory responses in the marrow and of fever shortly thereafter; (3) occurrence of a neutrophil nadir on the fourth to fifth day after onset of fever; (4) almost simultaneously, immune activation sufficient to neutralize viraemia and accelerate elimination of infected cells; (5) remission of symptoms; and (6) resolution of cytopenias. Clinical observations and experimental data bear on possible mechanisms of dengue virus-mediated marrow suppression. Work from the authors' laboratory in which long-term bone marrow cultures were used to investigate interactions between dengue virus and bone marrow cells (stromal elements and haematopoietic progenitors) is also reviewed. Long-term marrow culture (LTMC) was a useful experimental system. In vitro, early blast cells as well as the more differentiated haematopoietic elements were abortively infected, killed and eliminated by phagocytosis by specialized marrow macrophages called dendritic cells. Moreover, the ARC from stroma rather than haematopoietic precursors were productively infected. When ARC were infected, stroma failed to support haematopoiesis. Cytokine production by virus-infected stromal cells was altered. A hypothesis is proposed to account for dengue virus-induced marrow suppression. Down-regulation of haematopoiesis is probably a protective mechanism of the microenvironment that limits injury to the marrow stem/progenitor cell compartment during the subsequent process of elimination of infected cells.

Pathogenesis of feline panleukopenia virus and canine parvovirus

Feline panleukopenia virus (FPV) and canine parvovirus (CPV) are autonomous parvoviruses which infect cats or dogs, respectively. Both viruses cause an acute disease, with virus replicating for less than seven days before being cleared by the developing immune responses. The viruses have a broad tropism for mitotically active cells. In neonatal animals the viruses replicate in a large number of tissues, and FPV infection of the germinal epithelium of the cerebellum leads to cerebellar hypoplasia, while CPV may infect the hearts of neonatal pups, causing myocarditis. In older animals the virus replicates systemically, primarily in the primary and secondary lymphoid tissues, and also in the rapidly replicating cells of the small intestinal epithelial crypts. A transient panleukopenia or relative lymphopenia is often observed after FPV or CPV infection, respectively. Whether the reduction in cell numbers in vivo is due to virus replicating in and killing cells, or due to other indirect effects, is not known. However, FPV kills both erythroid and myeloid colony progenitors in in vitro bone marrow cultures, and it has been suggested that virus replication in the myeloid cells in vivo could lead to the reduced neutrophil levels seen after FPV infection of cats.