Comparing absolute lymphocyte count to total lymphocyte count, as a CD4 T cell surrogate, to initiate antiretroviral therapy

The predictive value of absolute lymphocyte counts on tumor progression and pseudoprogression in patients with glioblastoma

Background

Differentiating true glioblastoma multiforme (GBM) from pseudoprogression (PsP) remains a challenge with current standard magnetic resonance imaging (MRI). The objective of this study was to explore whether patients’ absolute lymphocyte count (ALC) levels can be utilized to predict true tumor progression and PsP.

Methods

Patients were considered eligible for the study if they had 1) GBM diagnosis, 2) a series of blood cell counts and clinical follow-ups, and 3) tumor progression documented by both MRI and pathology. Data analysis results include descriptive statistics, median (IQR) for continuous variables and count (%) for categorical variables, p values from Wilcoxon rank sum test or Fisher’s exact test for comparison, respectively, and Kaplan-Meier analysis for overall survival (OS). OS was defined as the time from patients’ second surgery to their time of death or last follow up if patients were still alive.

Results

78 patients were included in this study. The median age was 56 years. Median ALC dropped 34.5% from baseline 1400 cells/mm³ to 917 cells/mm³ after completion of radiation therapy (RT) and temozolomide (TMZ). All study patients had undergone surgical biopsy upon MRI-documented progression. 37 had true tumor progression (47.44%) and 41 had pseudoprogression (52.56%). ALC before RT/TMZ, post RT/TMZ and at the time of MRI-documented progression did not show significant difference between patients with true progression and PsP. Although not statistically significant, this study found that patients with true progression had worse OS compared to those with PsP (Hazard Ratio [HR] 1.44, 95% CI 0.86–2.43, P = 0.178). This study also found that patients with high ALC (dichotomized by median) post-radiation had longer OS.

Conclusion

Our results indicate that ALC level in GBM patients before or after treatment does not have predictive value for true disease progression or pseudoprogression. Patients with true progression had worse OS compared to those who had pseudoprogression. A larger sample size that includes CD4 cell counts may be needed to evaluate the PsP predictive value of peripheral blood biomarkers.

Acute hepatitis E virus infection causing acute liver failure requiring living-donor liver transplantation in a non-pregnant immunocompetent woman

We report a rare case of acute liver failure from acute hepatitis E virus (HEV) in a non-pregnant woman without comorbidities who survived after liver transplantation. The source was likely consumption of partially cooked pig liver. HEV genotype 3 is the second most common genotype causing acute hepatitis E in developed countries. Fulminant hepatitis E rarely occurs without a risk factor, as in our patient. Vigilant monitoring for chronic hepatitis E in post-transplant immunocompromised patients is needed.

Absolute Lymphocyte Count as a Surrogate Marker of CD4 Count in Monitoring HIV Infected Individuals: A Prospective Study

INTRODUCTION

CD4 cell count has been proposed to be substituted by Absolute lymphocyte count in monitoring HIV infected individuals as methods of CD4 cell count and plasma viral estimation require expensive, specialized equipments and highly trained personnel.

AIM

To assess the clinical utility of the Absolute Lymphocyte Count (ALC) to serve as a surrogate marker for predicting a CD4 count < 200 cells/μl in patients with HIV infection in resource poor countries.

MATERIALS AND METHODS

A prospective study of 61 patients with HIV/AIDS was conducted. Sensitivity, specificity, Positive Predictive Value (PPV), Negative Predictive Value (NPV) of various ALC cut-offs were computed for CD4 cell count < 200 cells/μl for age < 30 or age ≥ 30 years. Pearson correlation, Linear regression and Receiver Operating Characteristics (ROC), were used.

RESULTS

For patients aged ≥ 30 years, sensitivity, specificity, positive and negative predictive value of ALC <1200 cells/μl to predict CD4 cell count < 200 cells/μl were 34.48%, 67.5%, 43.48%, 58.69% respectively. For subjects aged < 30 years, these values were 27.27%, 67.5%, 18.75%, 77.14%, respectively. A ALC < 1643 was found to have maximal sensitivity for predicting a CD4 cell count <200/ μl.

CONCLUSION

Our data revealed good correlation between ALC and CD4 cell counts but ALC cut-off of 1200 was not a surrogate marker for CD4 cell count < 200 cells/μl. As we increase the cut-off to <1643/ μl it could be the cost-effective surrogate marker for CD4 cell counts < 200 cells/μl in resource limited settings.

A clinicopathological study of peripheral lymph nodes in HIV-infected patients with special reference to CD4+ T-cell counts: Experience from a tertiary care institution in Darjeeling (India)

BACKGROUND

HIV/AIDS is a major health burden worldwide. India bears the third highest HIV-patients load globally. In the Darjeeling district, HIV-prevalence is >1% with very little known about the profile of HIV-lymphadenopathy. The aim of this study was to identify the different causes of peripheral lymphadenopathy among HIV-infected patients in this region, correlate them with CD4+ T-cell counts and formulate some common clinico-haematological parameters as potential predictors of CD4+ T-cell count.

METHODS

In the present study, 76 cases were evaluated. Fine Needle Aspiration Cytology (FNAC) was performed as an out-patient procedure in the Department of Pathology. Smears were stained routinely with Haematoxylin-Eosin and Leishman stains. ZN stains were done when indicated by the cytological findings. Immediate CD4+ T-cell count was obtained by referring the patients to the Anti-retroviral therapy centre.

RESULTS

Cytological diagnoses included tuberculosis (82.9%), reactive hyperplasia (6.6%), nonspecific granulomatous lesions (3.9%), non-Hodgkin lymphoma (2.6%), histoplasmosis (2.6%) and simultaneous filariasis with toxoplasmosis (1.3%). Statistically, the opportunistic infections and lymphomas significantly concurred with a CD4+ T-cell count <350/μl. Likewise, the number of enlarged lymph nodes and absolute lymphocyte count (ALC) were found to be useful predictors of CD4+ T-cell counts.

CONCLUSIONS

Lymph node cytology in HIV-infected patients is essential to identify opportunistic infections from neoplastic lesions and; to enable therapeutic strategies. Correlation of lesions with mean CD4+ T-cell count predicts personal immunity, stage of disease and disease activity. Furthermore, enlarged lymph node numbers and ALC can be surrogate markers of CD4+ T-cell count for monitoring the severity of the immune suppression in under-resourced countries like India.

Derivation and validation of an accurate estimation of CD4 counts from the absolute lymphocyte count in virologically suppressed and immunologically reconstituted HIV infected adults

BACKGROUND

A simple method to estimate CD4 counts in stable, HIV infected virologically-suppressed and immune-reconstituted adults could save the expense of unnecessary formal testing.

METHODS

Using a baseline CD4 percent, CD4 counts were estimated from subsequent absolute lymphocyte counts (ALC) measured by an automated FBC machine (CD4 estimate calculated by the ALC multiplied by the baseline CD4 percent). The accuracy of this approach was established in a large, retrospective clinical laboratory dataset of virologically-suppressed HIV infected subjects. A case-control study explored important clinical factors for accurate estimates, and a heuristic algorithm was derived and validated in a random sample.

RESULTS

Data from 3,630 subjects were available. CD4 counts were generally accurately estimated, with a mean 6.1 % underestimation. Overall 83.3 % of CD4 estimates were within 25 % of the actual values, with 12.1 % CD4 counts underestimated by more than 25 %, and 4.5 % overestimated. The CD4 count was increasingly underestimated with time from baseline, and the degree of underestimation correlated with baseline CD4 percent (p < 0.0001). From the case-control study, baseline CD4 percent of ≥20, no illness requiring hospitalization and more than a year since starting or switch of anti-retroviral therapy were identified as significant predictors of inaccurate estimates. Employing this simple algorithm, CD4 estimate accuracy improved to a mean 1.3 % underestimation, and the proportion of estimates within 25 % of the actual value increased to 93.4 %.

CONCLUSIONS

In virologically-suppressed and immune-reconstituted HIV-infected adults, the CD4 count can be accurately estimated from the ALC using a baseline CD4 percent for at least 2 years after measurement.

Absolute lymphocyte count is not a suitable alternative to CD4 count for determining initiation of antiretroviral therapy in fiji

Introduction. An absolute lymphocyte count is commonly used as an alternative to a CD4 count to determine initiation of antiretroviral therapy for HIV-infected individuals in Fiji when a CD4 count is unavailable. Methods. We conducted a retrospective analysis of laboratory results of HIV-infected individuals registered at all HIV clinics in Fiji. Results. Paired absolute lymphocyte and CD4 counts were available for 101 HIV-infected individuals, and 96% had a CD4 count of ≤500 cells/mm(3). Correlation between the counts in individuals was poor (Spearman rank correlation r = 0.5). No absolute lymphocyte count could be determined in this population as a suitable surrogate for a CD4 count of either 350 cells/mm(3) or 500 cells/mm(3). The currently used absolute lymphocyte count of ≤2300 cells/μL had a positive predictive value of 87% but a negative predictive value of only 17% for a CD4 of ≤350 cells/mm(3) and if used as a surrogate for a CD4 of ≤500 cells/mm(3) it would result in all HIV-infected individuals receiving ART including those not yet eligible. Weight, CD4 count, and absolute lymphocyte count increased significantly at 3 months following ART initiation. Conclusions. Our findings do not support the use of absolute lymphocyte count to determine antiretroviral therapy initiation in Fiji.

Utility of absolute lymphocyte count as a surrogate marker of CD4 cell counts: Is it useful?

BACKGROUND

Human immunodeficiency virus (HIV) management has witnessed paradigm changes over the past decade. In the early era, Absolute lymphocyte counts (ALC) were used as an inexpensive, indirect marker of immunity status. With time, CD4 lymphocyte counts and HIV RNA levels have become a standard of care for follow up of people living with HIV/AIDS (PLHA). Wide disparities between resource rich and poor countries, rekindles the need for an inexpensive surrogate marker for CD4 lymphocyte counts. Multiple studies in the past including one by Sen S et al, in 2011 did not validate ALC as a surrogate marker of CD4 lymphocyte counts and had recommended a similar study at another centre to validate the same.(1) Recently few publications have suggested that ALC may be used as a proxy marker to CD4 lymphocyte counts in resource poor areas.(2) With this backdrop we decided to evaluate the association if any, of ALC as a surrogate marker to CD4 lymphocyte counts.

METHODS

ALC and CD4 lymphocyte counts measurements of 241 patients at our HIV/AIDS referral centre were assessed over a period of 13 months.

RESULTS

Pearson correlation coefficient, coefficient of determination and standard statistical methods revealed modest linear correlation between ALC and CD4 lymphocyte counts which was statistically significant but did not have clinical significance.

CONCLUSION

We recommend that time has come to call curtains down on ALC as a surrogate marker for CD4 lymphocyte count.

Zero CD4 count: a case of discordant CD4 response in a patient with well suppressed viral load

Human immunodeficiency virus (HIV) positive patients continue to have raise in CD4 cell for several years after initiation of anti-retroviral therapy (ART). The discordant response of static or fall in CD4 cells in presence of well-suppressed viral load is an unusual finding. In this communication, we present a case report of an HIV patient in whom the repeated CD4 enumerations consistently showed zero/nil CD4 counts before and after the start of ART in spite of maximum viral suppression.

HIV in the tropics: staging in the resource-limited setting

PURPOSE OF REVIEW

In 2010, the WHO updated HIV treatment guidelines for adults and children, expanding the eligibility of HIV-infected individuals for antiretroviral therapy (ART) on the basis of immunological staging. We discuss the barriers to HIV staging in under-resourced settings.

RECENT FINDINGS

In industrialized countries, HIV-infected patients are immunologically staged using CD4 lymphocyte counts measured using flow cytometry, but reliable and timely CD4 testing is still not readily available for all patients in many poorly resourced countries. Often CD4 testing is only available in central hospitals and clinics and depends upon availability of reagents. This leaves clinical staging as the standard of care in many places. Significant discrepancies exist between clinical and immunologic staging. Lack of immunologic staging can lead to delayed or inappropriate initiation of ART, increased attrition before ART, and overall poorer outcomes as patients often initiate ART at lower CD4 cell count baselines. This has led to intensive efforts to develop cost-effective laboratory testing, particularly for accurate low-cost CD4 testing.

SUMMARY

Simplified, low-cost alternatives for immunologic staging are vital to continued scale up of ART programs globally. Point-of-care CD4 testing in particular has shown promise in decreasing attrition rates before ART and improving overall mortality in resource-limited settings.