Amyloidosis: A changing clinical perspective

Primary amyloidosis is a plasma cell dyscrasia characterised by excess production of abnormal immunoglobulin light chains with their subsequent accumulation in kidneys, heart, liver as well as gastrointestinal tract and bone marrow 1-21, 2. These tissue deposits take the form of a fibrillar protein which damages the involved organ in proportion to the extent of the infiltration and roughly parallels the duration of the disease. Most cases have evidence of the underlying lymphoplasmacytoid neoplasm recognisable in two ways. Firstly, the monoclone appears in the serum [2]. Secondly is a morphologically and immunohistochemically distinctive cellular infiltrate in the bone marrow [3] that has a specific microscopic and ultrastructural pattern 4-54, 5. Interestingly occasional patients, who survive long enough, may progress to multiple myeloma [6] but the correlation is variable [7].

Coagulant and fibrinolytic status in tuberculous meningitis

BACKGROUND

The long-term neurologic sequelae of childhood tuberculous meningitis (TBM) mainly result from ischemia owing to cerebral vasculitis. Deep vein thrombosis occurs in adults with pulmonary tuberculosis owing to hypercoaguability. The present study aimed to investigate coagulation status during acute childhood TBM.

METHODS

Coagulation status, including the natural anticoagulants, antithrombin, protein C and protein S; procoagulant FVIII; fibrinolytic factors, tissue plasminogen activator and plasminogen activator inhibitor-1 (PAI-1) as well as anticardiolipin antibodies (ACA), was determined in 16 children with TBM before and during treatment.

RESULTS

A prothrombotic profile was found as expressed by a decrease of anticoagulant (protein S) and increase of the procoagulant (factor VIII) activity. Raised PAI-1 and normal tissue plasminogen activator values indicated deficient fibrinolysis. This hypercoagulable state was more pronounced in stage 3 patients than in stage 2 patients. The bleeding time on admission ranged from 1.2 to 10 minutes [mean 4.2 minutes]. The mean platelet count on admission was 577.9 +/- 188.6 x 10/L and increased further during the course of the treatment.

CONCLUSIONS

The hypercoagulable state in childhood TBM is comparable to that described in adults with pulmonary tuberculosis and may further increase the risk for infarction. Therapeutic measures that reduce the risk for thrombosis could therefore be potentially beneficial in childhood TBM.

Lack of clinical manifestation of hereditary haemochromatosis in South African patients with multiple sclerosis

Caucasian South African patients with multiple sclerosis (MS) were screened for the most common hereditary haemochromatosis (HH) mutations, H63D and C282Y, in order to determine the impact of iron overload on clinical outcome of MS. DNA screening for mutations H63D and C282Y in 118 apparently unrelated MS patients did not reveal significant differences in allele frequencies in comparison with a control group from the same population. Of 17 MS patients heterozygous for C282Y, 3 had below normal and none had above normal transferrin saturation levels. One of the index MS patients, and subsequently also her sister who also has MS, tested positive for two copies of mutation C282Y. Determination of iron status revealed high serum ferritin and transferrin saturation levels in both patients. However, the index patient, being unaware of her C282Y status, had received treatment for iron deficiency in the past and her MS symptoms were less severe than those of her sister who has been wheelchair bound for the past 12 years and who did not take iron supplements. Lack of clinical manifestation of HH without any signs of organ damage in the C282Y homozygous MS patients is in accordance with a role of iron dysregulation in the aetiology of MS.

Clinical rotation in pathology: description of a case based approach

BACKGROUND

The implementation of a system based, integrated curriculum at the Faculty of Health Sciences of Stellenbosch University, Western Cape, South Africa, resulted in less contact time for the pathology disciplines during theoretical modules, while a weekly rotation in pathology was introduced during clinical training in the fourth and fifth years.

OBJECTIVE

To describe a problem based approach for this rotation.

METHODS

Students are presented with a clinical "paper" case daily, integrating as many of the pathology disciplines as possible to demonstrate the interdependence of the various disciplines. They receive chemical pathology tutorials, visit the various laboratories, and receive practical training in fine needle aspiration biopsy. On the final day, the case studies are assessed and discussed.

RESULTS

Most students appreciated all activities. This rotation enhanced student interactivity and autonomy and guaranteed immediate feedback. On evaluation of the rotation it was found that the students enjoyed the rotation, learnt something new, and realised the value of group work.

CONCLUSIONS

This innovation integrates pathology with clinical practice and illustrates the use of laboratory medicine in the management of common diseases seen in this country. Students appreciate learning practical skills and having to request special investigations under a pathologist's supervision changes their approach to pathology requests. Familiarity with the pathology environment empowers the student to use pathology with greater ease. A bank of case studies that can be expanded to include all medical disciplines will facilitate the application of a problem based approach and enhance communication between the basic science disciplines and the clinical and pathology disciplines.

The 2000 Burkitt lymphoma trial in Malawi

BACKGROUND

We previously reported 57% 12-month event free survival (EFS) in Malawian children with stage I to III Burkitt lymphoma (BL) with an intermediate dose chemotherapy protocol lasting 77 days. This protocol was shortened to 42 days and evaluated in children with stage I to IV disease for EFS and toxicity.

METHODS

All Malawian children admitted to Queen Elizabeth Central Hospital, from 03/08/2000 to 12/03/2002 with confirmed BL were eligible. A fine needle aspirate, bone marrow aspirate, cerebrospinal fluid cytology, haemoglobin (Hb), white cell count (WCC), malaria smear, ELISA for HIV, and abdominal ultrasound were performed routinely. Murphy staging was used. The first dose of chemotherapy (COP1) consisted of 300 mg cyclophosphamide (CPM), 1 mg vincristine, and 60 mg prednisone given on day 1 and followed by COP2 on day 8 (only for patients with larger tumour volumes, stage III or IV disease). The vincristine dose in COP2 was 2 mg. COMP1 and 2 given on days 22 and 36 consisted of 500 mg CPM, 2 mg vincristine, 60 mg prednisone, and 2 g methotrexate. All doses were calculated per body surface area. Intrathecal methotrexate and hydrocortisone were given with COP1 and 2.

RESULTS

Forty-two patients, 30 boys and 12 girls median ages 6 and 7.5 years, respectively, had Murphy stage I(n5), II(n8), III(n21), and IV(n8) disease. The face was involved in 74%, abdomen in 55%, bone marrow in 14%, kidneys in 24%, and 12% had paraplegia. Fourteen children died during or shortly after completion of chemotherapy. Three of these were disease related. Twelve patients suffered a local relapse after 57-328 days, and one a CNS relapse at 76 days. The projected EFS at 12 months is 50% in stage I, 50% in stage II, 24% in stage III, 25% in stage IV, and 33% for all patients. The cumulative mean dose of CPM was 62 mg/kg in survivors and 64 mg/kg in children who relapsed. One third of patients experienced significant marrow suppression, and infections after COMP1.

CONCLUSIONS

Thirty-three percent of children are in first remission at 12 months. The morbidity and mortality of treatment was high. The high relapse rate in all stages may be due to the low cumulative dose of CPM.

Prenatal diagnosis of congenital leukemia in a fetus at 25 weeks' gestation with Down syndrome: case report and review of the literature

Leukemia in a hydropic fetus with hepatosplenomegaly and Down syndrome was diagnosed at 25 weeks' gestation. Spontaneous demise occurred 10 days after the cordocentesis. A review of the literature of the seven cases described antenatally and 10 cases described in the immediate neonatal period or on examination of the stillborn baby is presented.

Band 3 Cape Town (E90K) causes severe hereditary spherocytosis in combination with band 3 Prague III

Hereditary spherocytosis (HS) is an inherited haemolytic anaemia, characterized by spheroidal, osmotically fragile red blood cells. This disorder exhibits heterogeneity in terms of both clinical severity and underlying molecular defect. We have studied a South African Cape Coloured individual with severe HS owing to a band 3 deficiency caused by two mutations, occurring in trans, in the band 3 gene: a novel variant that we have designated band 3 Cape Town and a previously described mutation, band 3 Prague III. Analysis of erythrocyte membrane proteins indicated a deficiency of both band 3 and protein 4.2, as well as a decreased functional capacity of band 3 to transport anions. Band 3 Cape Town is defined by a GAG-->AAG point mutation at codon 90, substituting a glutamic acid with a lysine in the cytoplasmic domain of the molecule, while band 3 Prague III is a codon 870 CGG-->TGG point mutation, replacing an arginine with a tryptophan in the transmembrane region of band 3. mRNA is transcribed from both mutant alleles, implying that mutant proteins are synthesized, but are either degraded prior to membrane incorporation or insertion is impaired. We conclude that the combination of these two mutations exacerbated the clinical presentation of the proband.

Serum concentrations of some metals and steroids in patients with chronic fatigue syndrome with reference to neurological and cognitive abnormalities

Chronic fatigue syndrome is defined by the Atlanta Centers for Disease Control (Atlanta, GA, USA) as debilitating fatigue lasting for longer than 6 months. Symptoms include disturbances of cognition. Certain factors have in the past been shown to influence cognition, including metals such as aluminum, iron, and zinc; and steroids such as dehydroepiandrosterone. In the present study, concentrations of these factors were determined in the serum and plasma of patients and their age- and gender-matched healthy controls (10 women and 5 men in each group). In addition, copper, dehydroepiandrosterone sulphate, cortisol, cholesterol, hemoglobin, ferritin and transferrin concentrations, as well as transferrin genetic subtypes were determined in both groups. The results indicate that patients had significantly increased serum aluminum and decreased iron compared to controls. In the females, serum iron and dehydroepiandrosterone sulphate were significantly decreased and correlated. Total cholesterol was significantly increased, and significantly negatively correlated with dehydroepiandrosterone sulphate. There were no differences in zinc, copper, cortisol, hemoglobin, transferrin and ferritin concentrations, or in transferrin genetic subtypes.