Jr Bhardwaj

MICROWAVE STIMULATED FIXATION AND RAPID PROCESSING OF TISSUE FOR HISTOPATHOLOGY

A rapid method for obtaining high quality paraffin sections is described. This method enables preparation of paraffin blocks in about 20 minutes and is based on microwave stimulated tissue fixation and processing. A total of 200 tissues were processed. Tissue blocks of size 1×1×0.5 were found ideal for processing. Three protocols were evaluated for tissue processing using different timings of exposure to graded alcohols, chloroform and wax. It was observed that utilizing an additional step of exposure to 70 per cent alcohol during tissue dehydration resulted in preparation of paraffin blocks which were light microscopically excellent and highly comparable to conventional methods.

THE CD 10 MARKER IN THE INVESTIGATION OF ACUTE LYMPHOBLASTIC LEUKAEMIA

Immunophenotyping of leukaemias is presently well established. It is invaluable for proper case management [1]. The most useful information on the management of cases of Acute Lymphocytic Leukaemia (ALL) is provided by the detection of the CD 10 marker on the leukaemic cell. The CD 10 positive ALL has since long been associated with a favourable prognosis as compared to the CD 10 negative ALL [1, 2]. As immunophenotyping is resource intensive, the monoclonal antibodies (MO ABS), are not in widespread use in our country. The expenses involved make this procedure prohibitive in most institutions. For this reason, a limited panel of MO ABS has been used in this study, with a special emphasis on the CD 10 marker. A total of 25 cases of ALL were studied. 17 cases were found to be positive for the CD 10 marker (68%). These cases were associated with a favourable prognosis as compared to the CD 10 negative group. Although, the diagnosis of ALL and leukaemias in general, is essentially based on the study of Romanowsky stained smears [3, 4], the additional information provided by the cell surface marker study results in better case management [1].

EARLY DIAGNOSIS IN POST RENAL TRANSPLANT OPPORTUNISTIC INFECTIONS: A FRESH LOOK

A total of 86 renal transplant patients who were transplanted with live related donor (LRD) and live unrelated donor (LURD) kidneys were studied for opportunistic infections. Immune diagnosis of Toxoplasma, Cytomegalovirus (CMV), Herpes-simplex virus type II (HSV-2), Aspergillosis and Tuberculosis was carried out in these patients along with sputum examination, CSF studies and biopsy of lymphnode and other tissues in few cases. A high degree of Toxoplasma, CMV & HSV-2 positivity was seen in transplanted patients. However sensitivity of serological diagnosis of tuberculos was found to be low with standard criteria, which increased significantly when modified criteria were used. It is concluded that regular immunological monitoring should be carried out in transplanted patients so as to reach an early diagnosis and management of opportunistic infections.

HELICOBACTER PYLORI AND GASTRIC CANCER: IS THERE A LINK?

This paper examines the correlation between prevalence of H pylori, gastritis and the histological type of gastric cancer. 50 gastrectomy specimens from the patients with gastric cancers were studied for the prevalence of H pylori, type of gastritis as classified by the Sydney system, presence of intestinal metaplasia, and the histological type of gastric cancer. H pylori was detected in 27 (54%) stomachs. The common site for finding this bacterium was either antrum or body of stomach (16 and 17 sections respectively), Gastritis was found in 48/50 specimen (96%) from non-neoplastic areas. However, 15 of the 18 patients with atrophic gastritis had H pylori in their stomach specimens either in the body or in antrum. Intestinal metaplasia was detected in 19 (38%) specimen. Of these, 14 (73.7%) specimens had type 1 and remaining 5 (26.3%) had type 2 metaplasia. The distribution of metaplasia was significantly more in H pylori positive patients. Prevalence of H pylori positivity was highest in intestinal type of cancer (66.7%) and lowest in diffuse variety (45.8%). In two third specimens of intestinal type of cancer, gastritis was related to H pylori while such association with H pylori was seen in approximately half (45.8% & 57.1% respectively) the specimens of other types of cancers. There is strong association between the prevalence of H pylori and gastritis on one hand and the intestinal metaplasia on the other, in patients with gastric cancer. These findings, indirectly support Correas hypothesis that H pylori is a causal factor in the intestinal form of gastric cancer.

IMPORTANCE OF PROSTATIC SPECIFIC ANTIGEN (PSA) IN CLINICAL PRACTICE : OUR EXPERIENCE

A total of 89 patients in the age group of 50-92 years having different histopathologically proven prostatic conditions were analysed with prostate specific antigen (PSA) and clinical co-relation undertaken. PSA levels were found to be significantly higher (p < 0.05) in 48 carcinoma prostate cases (mean 93.16 ± 50.75 ng/ml) as compared to 32 benign prostatic hyperplasia (mean 4.66 ± 3.85 ng/ml). Similarly, levels were considerably reduced in 15 post-operative adenocarcinoma cases (mean 10.77 ± 9.65 ng/ml) as compared to their pre-operative samples (mean 93.16 ± 60.75 ng/ml). PSA levels were moderately higher in 9 cases of prostatitis (mean 13.28 ± 4.53 ng/ml). A very high degree of sensitivity, specificity and positive predictive value of PSA e.g. 95.8%, 75.6% and 82.2% respectively was found in adenocarcinoma cases, when levels of PSA were > 10 ng/ml. Thus it necessitates a detailed and thorough examination in such cases to come to final conclusion and early management of the cases.

TOXOPLASMA ENCEPHALITIS (TE): A REPORT ON THREE FATAL CASES

Toxoplasma gondii is a ubiquitous protozoan parasite. Humans are accidental dead end hosts, cat being the definitive host. Since the advent of AIDS, the impact of infection with this protozoan has been fully appreciated [1]. Toxoplasmosis and toxoplasma infection are two different terminologies, the former describes an active disease process whereas the latter is defined by the mere presence of viable organisms [2]. Chronic or latent infection is present in all those infected since the parasite resides in the cystic stage in some tissues without any clinical disease. Reactivation occurs in immunocompromised patients [3]. The parasite is acquired per-orally, transplacentally or rarely, parenterally in laboratory accidents, by transfusion, or from a transplanted organ. Individuals with HIV infection/AIDS frequently develop toxoplasmosis; the disease usually involves CNS and is often fatal [1]. Toxoplasma Encephalitis (TE) is the most common presentation of toxoplasmosis in AIDS patients [4]. About one third of the patients with AIDS who are latently infected with the parasite will develop TE [5]. Congenital infection is considered to occur only when primary infection is acquired during gestation [6]. Immunocompromised women who acquire the primary infection within 6-8 weeks before conceiving are an exception to the above [7]. The risk of infection to the fetus varies with the trimester of gestation when the mother becomes infected, and increases with the period of gestation. We report below the 3 fatal cases of toxoplasmosis, including a case of congenital toxoplasmosis, to highlight the multiorgan disease, dominant CNS involvement and fatality caused therefrom, in the HIV infected group. Fatal Case No.1 A 39-year-old male presented with dry cough and fever of 2 weeks and cervical lymphadenopathy of 4 weeks duration FNAC of the lymph node showed evidence of tuberculosis. After one month of ATT, he developed eighth nerve palsy on the left side. CT scan of the brain revealed a large irregular ring enhancing lesion 3 cms in diameter in the left parietal region. Within a week after CT scan he developed signs of meningoencephalitis. A repeat CT scan revealed a space occupying lesion with compressed lateral ventricles, reported as tuberculoma of the brain. CSF showed raised proteins (80 mg/dL) with pleocytosis (20 lymphocytes/cmm). At this juncture, serum was tested for HIV and was positive for anti-HIV antibodies. Serum and CSF were strongly positive for toxoplasma IgG antibodies and borderline positive for IgM antibodies. He was put on therapy for toxoplasmosis and ATT was continued. He progressed in to coma and died. Autopsy was not carried out.

IMMUNOBIOLOGICAL MONITORING OF VARIOUS GASTROINTESTINAL AND PRIMARY HEPATIC MALIGNANCIES

Carcinoembryonic antigen (CEA) and alpha fetoprotein levels (AFP) were assayed by enzyme-labelled immunoassay in 75 cases of gastrointestinal (GI) and primary hepatic malignancies. Mean CEA levels were found to be significantly higher (p<0.005) in metastatic non-operative group of GI malignancies (range 5.32 ng/mL to 175.2 ng/mL) as compared to early pre-operative cases (range 1.25 ng/mL to 33.2 ng/mL) and post-operative cases (range 1.41 ng/mL to 22.24 ng/mL). Variable levels of AFP were visualised in 12 cases of primary hepatic malignancies with eight cases having values less than 100 ng/mL. When both CEA and AFP were assayed simultaneously, the markers were helpful in differentiating cases of primary hepatic malignancies with low levels of CEA from 3 cases of secondaries in the liver where CEA levels were found to be highly raised (80.4 ng/mL to 146.4 ng/mL). To evaluate the variation of CEA and AFP levels in different patients having same stage of the disease, immunological monitoring for the functions of T and B cells was carried out by estimation of cytokine, i.e. interleukin-1 alpha (IL-1a), interleukin-2R (II-2R) and various immunoglobulins. IL-1a and 1L-2R levels were significantly higher (p<0.05) in the groups of patients having higher CEA and AFP. This indicates an important T cell (TH1 and TH2) function in the tumour antigen production.

HORMONAL MARKERS IN THE STUDY OF PITUITARY ADENOMAS

Twenty pituitary adenomas were studied using light microscopy, immunohistochemistry and electron microscopy. Based on clinical manifestations of hormonal hypersecretion they were divided into two groups, i.e. group-I (12 patients) with no endocrine dysfunction and group-II (8 patients) with endocrine dysfunction. Group-I could be further sub-divided into two groups based on IHC : group LA in which no hormone could be localised in the tissue (null cell adenomas) and group IB where hormones could be localised in the tissue (1). Tumours in group II, with light microscopy, were acidophil (n=5), basophil (n=1) or mixed (n=2) adenomas. Eight of these 20 cases were plurihormonal. Growth hormone, and prolactin were the commonest combination. This study has helped in the reclassification of the pituitary adenomas according to the hormone they produce.

SELLAR CHONDROID CHORDOMA: A Case Report

C hordomas are uncommon neoplasms. They arise from the remnants of the notochord and hence are seen in close relation to the axial skeleton. Sites usually involved are the sacrococcygeal and the sphenooccipital regions [1,2]. Chordomas containing prominent chondroid elements have been termed as chondroid chor› doma [3]. They are slow growing tumours which infiltrate adjacent structures and stubbornly recur after excision. Distant metastases are rare and oc› cur late in the disease [3,4].

LEUKAEMIC INVOLVEMENT OF CENTRAL NERVOUS SYSTEM

Eighty two patients of leukaemia consisting of 25 cases of acute lymphocytic leukaemia, 38 cases of acute myeloid leukaemia, 14 cases of chronic myeloid leukaemia and 5 cases of chronic lymphocytic leukaemia were evaluated for central nervous system (CNS) involvement. Speech disorders, cranial nerve palsies, encephalopathy, ataxia, intracranial haemorrhage, peripheral neuropathy and spinal cord involvement were the main neurological findings detected in 23 (28.1%) cases. All except one were subjected to autopsy after death. Leukaemic infiltrations (36.6%) and intracranial haemorrhage (26.8%) were the prominent CNS autopsy findings. In addition, demyelination with astrocytosis (9.7%) and gliosis (2.4%) were seen. In all, 45 (54.9%) of the patients showed CNS involvement at autopsy. Thus a large number of CNS lesions were missed clinically and detected only on autopsy.