Contamination of cerebrospinal fluid by vertebral bone-marrow cells during lumbar puncture

Lowering Platelet Threshold to 20,000/μL for Fluoroscopy-Guided Lumbar Puncture Does Not Result in Observed Clinical Adverse Outcomes

PURPOSE

Fluoroscopic-guided lumbar puncture (FG-LP) is a common neuroradiologic procedure. Traditionally, a minimum platelet count (MPC) of 50,000/μL for this procedure has been required; however, we recently adopted a lower MPC threshold of 20,000/μL. The purpose of this study was to compare adverse events in patients undergoing FG-LP with MPCs above to those below the conventional 50,000/μL threshold.

MATERIALS

This was an institutional review board-approved, retrospective study on adult patients with hematologic malignancy undergoing FG-LP in the neuroradiology division between May 2021 and December 2022, after lowering the minimal required MPC to 20,000/μL. Recorded data included indication for FG-LP, preprocedure and postprocedure MPC, need for and number of platelet transfusions within 24 hours of FG-LP, presence of traumatic tap, FG-LP-related complications, and any platelet transfusion-related adverse event. Patients were classified into 2 groups based on MPC: (1) those above 50,000/μL and (2) those below 50,000/μL. Descriptive statistics were used comparing these 2 groups.

RESULTS

One hundred twenty-eight patients underwent FG-LP, with 46 having an MPC between 20,000 and 50,000/μL and 82 having an MPC above 50,000/μL. No postprocedural complications were encountered in either group. Traumatic taps occurred in 10/46 (22%)​ with MPC below 50,000/μL versus 10/82 (12%)​ in those with MPC above 50,000/μL. Forty of 46 patients (87%) were transfused with platelets within 24 hours prior to FG-LP. One patient developed a transfusion-related reaction.

CONCLUSION

Lowering the MPC threshold from 50,000/μL to 20,000/μL for FG-LP did not result in a higher incidence of spinal hematoma.

Bone marrow elements in cerebrospinal fluid: Review of literature with a case study

Presence of bone marrow elements in cerebrospinal fluid is rare. Journal publications on this topic are few and majority of them were written over a decade ago mostly as case reports in young children or the elderly. The increased cellularity and presence of myeloid precursors can be a pitfall and may be misdiagnosed as leukemia or lymphoma or central nervous system infection, when the specimen is actually not representative. With the intention to create awareness of potential pitfalls and avoid erroneous diagnoses, as well as adding on to the current photo archive of bone marrow elements in CSF, we present a recent case of bone marrow contaminants in the CSF of a 16-year-old girl.

The influence of traumatic lumbar puncture and timing of intrathecal therapy on outcome of pediatric acute lymphoblastic leukemia

The CNS is a frequent site of relapse of childhood acute lymphoblastic leukemia (ALL). Traumatic lumbar puncture (TLP) is thought to increase the risk of CNS relapse. The authors examined whether TLP at the time of diagnosis affected outcome and whether this effect was influenced by the timing of intrathecal therapy (IT) in 77 patients with newly diagnosed ALL. IT was instilled at the time of either the diagnostic LP (early) or a second LP 24--48 h later (delayed). Of the 19 patients who had a TLP at diagnosis and received late IT therapy, 6 had isolated CNS relapse and 2 had combined CNS and bone marrow (BM) relapse. Of the 9 patients who had TLP and received early IT therapy, 1 had a CNS relapse (p=.20). In an analysis stratified according to risk of relapse, the odds ratio (OR) for relapse was 0.8 among patients at low and standard risk who had delayed IT therapy after TLP (p=.99) vs. 0.17 for those who had early IT (p=.47). Importantly, among patients with high-risk ALL, the OR for relapse was 21.0 for delayed IT therapy (p=.09) and only 1.5 for early IT therapy after TLP (p=.99). The results indicate that TLP at diagnosis appears to increase the risk of CNS relapse markedly in patients with high-risk ALL, and the use of early IT therapy appears to reduce this risk. These findings need to be confirmed by prospective, randomized studies.

Bone marrow contamination of canine cerebrospinal fluid

Bone marrow cells were identified in cytocentrifuge preparations of cerebrospinal fluid (CSF) obtained by lumbar punctures from two dogs. CSF analyses were characterized by normal or increased total cell counts, normal or increased total protein concentration and the presence of erythrocytes. Hematopoietic cells present included both erythroid and myeloid precursors and, in one case, an erythroblastic island was seen. Peripheral blood smear examination confirmed that the hematopoietic cells observed were not the result of blood contamination. Neither case was associated with a difficult tap procedure, nor with a specific disease process. Contamination may have resulted from actual marrow penetration or from extramedullary hematopoiesis in the dura mater. Accurate interpretation of CSF cytology requires the consideration of possible bone marrow contamination when hematopoietic cells are observed.

Value of cerebrospinal fluid examination in the diagnosis of meningitis in the newborn

Between 1 October 1988 and 30 September 1991 the results of all 896 cerebrospinal fluid examinations from 736 neonates were correlated with clinical diagnosis, treatment, and outcome. The prevalence of fungal or bacterial meningitis in babies requiring lumbar puncture was only 0.95%. Gram staining had a sensitivity of 68% and a positive predictive value of only 46% for the diagnosis of meningitis. Primary cultures directly onto agar plates had a sensitivity of 81% and positive predictive value of 46%. Broth enrichment cultures did not improve sensitivity and were frequently found to be false positive. Empirical treatment should not be altered unless more than a few organisms are seen on Gram staining. Primary cultures are adequate for the diagnosis of fungal and bacterial meningitis. Enrichment cultures should be performed only when the Gram stain and/or cell count suggests meningitis is likely. Clinicians should be aware that diagnostic tests performed in populations with a low prevalence of disease are likely to generate many false positive results and have a low positive predictive value.

Humoral CSF parameters in the differential diagnosis of hematologic CNS neoplasia

Cerebrospinal fluid (CSF) and serum samples of 20 patients with central nervous system manifestations of hematological malignancies including primary cerebral lymphoma (n = 5) and disseminated non-Hodgkin lymphoma (n = 7) were examined for albumin, IgG, IgM, fibronectin, beta 2-microglobulin, interleukin-6, soluble interleukin-2 receptor, tumor necrosis factor alpha, and oligoclonal immunoglobulin bands. Although a broad range of abnormalities were detected, no reliable CSF parameter for the diagnosis of leptomeningeal spread from hematological neoplasias could be identified. An analysis of 61 repeat lumbar punctures added little to the findings of the first CSF examinations. Currently, immunochemical studies of CSF cell surface markers and early biopsy have probably more clinical value than the determination of the humoral CSF parameters included in this study. However, analysis of cytokine synthesis by single CSF cells using molecular biology techniques may improve the differential diagnosis of hematological neoplasia of the brain and spinal cord in the future.

Megakaryocytes in fine-needle aspiration biopsy of breast

An unusual case in which megakaryocytes were found in fine needle aspirate of a breast lesion is reported. The megakaryocytes in the smears were initially mistaken to be malignant cells. However, the cell block sections available later showed normal bone marrow particles, indicating that an inadvertent puncture of a rib was the reason for the presence of megakaryocytes in the smears.

Malignancy markers in the cerebrospinal fluid

The specificity and sensitivity of malignancy marker determinations in cerebrospinal fluid (CSF) are often insufficient. Even at the subclinical stage of the disease the marker should be present. The effect of therapy should be monitored and relapses noted. Thus high standards of methodology are required. There are many substances that may indicate a malignant process in the central nervous system. However, there are many pitfalls in their determination. Malignant cells may occur in CSF via processes involving leptomeningeal structures such as metastases and leukaemia, but primary brain tumours seldom show cells in CSF. Human chorionic gonadotrophin and alpha-fetoprotein determinations assist in the early detection of cerebral germ cell tumours and of relapses, even in the subclinical stage. Desmosterol may aid in the diagnosis of medulloblastomas and malignant gliomas and in monitoring therapy. Putrescine levels are elevated in CSF of patients with medulloblastoma and correlate with the clinical state, and serial analyses may reveal relapses. Fibronectin, when determined in CSF at the time of diagnosis, appears to be of great significance for the prognosis of acute lymphoblastic leukaemia. Ferritin and beta-2-microglobulin may help in some well-defined conditions. Brain-specific proteins and antibodies to them are non-specific markers whereas tumour-specific antigens and growth factors may be more significant.

Diagnosis of meningeal involvement in childhood acute lymphoblastic leukemia: cytomorphology and TdT

Between December, 1984, and May, 1986, 98 CSF samples were sent to a central laboratory by postal express. The samples could be kept in a medium for up to 24 hours after the lumbar puncture. The quality of the cells proved to be good. Excluded were 5 samples delayed in delivery and 13 samples contaminated with blood, defined as the macroscopical presence of blood. The microscopical presence of erythrocytes in the cytocentrifuge preparation can make interpretation of the results difficult. Especially when leukemic blasts are present in the blood, extreme caution is necessary. A total of 71 samples could be studied by cytomorphology as well as by TdT-IF. When cytomorphological leukemic blasts were present, this was confirmed by TdT-IF positivity in all cases. But in 6 of 71 samples, TdT-IF was positive without the presence of cytomorphological leukemic blasts. Follow-up of these patients will show whether the therapeutic regimen has to be changed.

Central nervous system involvement in acute nonlymphocytic leukemia. A prospective study of adults in remission

To identify adults with acute nonlymphocytic leukemia at risk for the development of central nervous system involvement, we performed periodic cerebrospinal fluid examinations on patients in remission. Among 58 consecutive patients monitored during first remission, central nervous system leukemia developed in nine (16 percent). Four patients, including one who was symptomatic, had central nervous system leukemia detected simultaneously with marrow relapse. Five additional patients were asymptomatic and continue to have bone marrow remission. Following central nervous system and systemic treatment, two of these five patients have never had relapse, and three had relapse in the bone marrow five, 10, and 21 months later. Factors at diagnosis associated with the subsequent development of central nervous system leukemia were elevated leukocyte count, serum lysozyme and lactate dehydrogenase, extramedullary infiltration including splenomegaly, and monocytic (FAB M4 or M5a) morphology. In six of 17 patients (35 percent) with monocytic morphology, central nervous system leukemia developed compared with only three of 41 patients (7 percent) with other subtypes (p = 0.02). Discriminant analysis identified leukocyte count, splenomegaly, and M4 or M5a morphology as the most important risk factors and led to a mathematical formula that correctly identified 90 percent of the patients. Although the risk of central nervous system leukemia in adults with acute nonlymphocytic leukemia is too low to justify routine prophylaxis, those patients recognized to be at a greater risk should receive prophylaxis or be monitored closely with periodic lumbar punctures.