285

require chronic pharmacotherapy as part of their treatment, intensifying the need for investigation of this possible side-effect. Department of Psychiatry, School of Medicine, Wayne State University, and Lafayette Clinic, Detroit, Michigan 48207, U.S.A. Center in Environmental Toxicology, Department of Biochemistry, School of Medicine, Vanderbilt University, Nashville, Tennessee 37235, U.S.A.

SERUM-COPPER IN SICKLE-CELL ANÆMIA SIR,—Increased serum-copper concentrations have been reported in various haematological disorders, such as

thalassasmia, aplastic anaemia, pernicious anaemia,l.2 and in the lymphoreticular disorders. There are no previous of serum-copper in sickle-cell et al.,4 using the rubeanic acid staining technique, demonstrated excessive amounts of copper granules in erythrocytes containing S haemoglobin. Copper-staining granules were absent in normal (AA) erythrocytes. The importance of the increased copper content in sickled erythrocytes is unknown. We have measured serum-copper by atomic absorption spectrophotometry in a total of 217 subjects as previously described.5 72 of them had sickle-cell anxmia (SS), 46 were cases of sickle-cell haemoglobin C disease (SC), 32 had the sickle-cell trait (AS), and the remaining 67 were

reports of

JOHN M. RAINEY, JR.

R. A. NEAL.

A NEW SPECIES OF MICROFILARIA ? eastern zone of the Indian subcontinent is endemic area of filariasis, which is particularly common in West Bengal, Orissa, and Assam. In West Bengal, the common infecting species of microfilaria is Wuchereria bancrofti. Similar species of microfilaria has been detected in the district of Bankura, in the western mountainous region of West Bengal. Besides W. bancrofti a new species of microfilaria has often been seen in the peripheral blood of patients in this district. The microfilaria is a sheathed one and commonly found in the blood during daytime. Although the size, shape, and arrangement of the somatic

SiR,—The

an

SERUM-COPPER LEVELS IN

nuclei of this newly isolated species are similar to those of W. bancrofti, the cuticular structure is striated transversely from the head to tail. These striations are seen clearly under phase-contrast microscope and distinctly noticed after Giemsa or Leishman stain (see accompanying figure). Further serological study will help to confirm this newly isolated species of microfilaria. The clinical signs and symptoms produced by infection with this particular species of microfilaria are similar to those of classical W. bancrofti infection-fever, lymphangitis, and lymphadenitis. The disease responds to treatment with diethylcarbamazine.

INDIVIDUALS

S. K. BISWAS S. C. SAHA M. CHOUDHURY.

0.001 and f p < 0-025 when these groups normal individuals.

are

compared with

normal controls (AA). The haemoglobin types had preelectrophoresis on viously been established by low-voltage filter paper as previously described.6 The average serum-copper level in patients with SS was significantly increased in comparison with the control group (AA) (p < 0-001) (see accompanying table). Similarly, the serum-copper in patients with SC was significantly increased in comparison with normal controls (AA) (p < 0-025). The serum-copper levels in normal controls (AA) were identical with the levels in individuals carrying AS. Serum-copper in SS was significantly higher than in SC (P< 0-025). A reduction in plasma-zinc in sickle-cell ansemia has been reported 7,and copper and zinc, together with calcium,9 sodium, and potassium 10 may be involved in the maintenance of the structural integrity of the redblood-cell membrane. In the development of irreversible sickling there is a net gain in red-blood-cell calcium9 and sodium 10 and a net reduction in potassium.1O The changes’ in the serum levels of these metals could therefore provide an index of the amount of irreversible sickling that has taken place. 1. 2. 3.

4. 5. 6. 7. 8.

Department of Pathology and Bacteriology, B.S. Medical College, Bankura, West Bengal, India.

SS, SC, AND AS PATIENTS AND IN NORMAL

.

p
_02 µg. per ml.) were found in the serum for 8 days, falling from 0-8 µg. per ml. on the first two days after therapy to 02 µg. per ml. on the 8th day. In the urine gentamicin could be detected for up to 20 days: 7-8 µg. per ml. on the first two days, falling to about 0.2 tLg. per ml. on the 20th day. From the 2nd to the 20th day after therapy approximately 15 mg. gentamicin was recovered in the urine (i.e., nearly 8% of the total dose). The assays were carried out by agar-well diffusion. When adding anti-gentamicin antiserum 6 to the urine no zones of inhibition were obtained. The specificity of the assays was further checked by determining serum and urine concentrations with a radioimmunological technique.6 The low recovery during therapy and the prolonged excretion after the last dose point to accumulation of the drug followed by a slow release. Red blood-cells may have the capacity to take up gentamicin and thus influence the pharmacokinetic properties of the drug: in patients with high haematocrit low and sustained serum levels were found.’ This suggestion would fit our case since the serum levels during therapy were unexpectedly low and his hæmatocrit was 57-60%. However, in-vitro tests with fresh cells from the patient and blood-donors provided no evidence of uptake of gentamicin by red blood-cells. An investigation now in progress indicates that an accumulation of gentamicin often occurs in patients on i.m. therapy, followed by a slow release of the drug. Perhaps our patient represents a rule rather than an exception. Other tissues than erythrocytes seem to bind the drug. Perhaps some i.m. gentamicin is taken up at the site of injection, and repeated injections at the same site may enhance uptake.

THYROTROPHIN-RELEASING HORMONE IN DEPRESSION were reported by Dr Coppen and results SIR,—Negative his colleagues (Aug. 24, p. 433) with thyrotrophin-releasing hormone in the treatment of depression. In their first trial, Hamilton’s rating scale was applied at 3-hourly intervals and later at 6-hourly and 12-hourly intervals as the only measure of change. In the second trial the Hamilton rating scale

was applied twice weekly 2-hourly for the first 6 hours.

and the 100

mm.

line test

We submit that the authors have misused the Hamilton to measure short-term change with it. It was devised to record the severity of symptoms rather than minor fluctuations; and Hamilton instructs8 that,questioning on all items should be directed to the patients’ condition in the past few days or week. Items concerned with insomnia (items 4, 5, 6), time spent in work activity (7), loss of libido (14), and loss of weight (16) are obvious examples of symptoms that would not fluctuate in 3 hours. The objective of the first trial has been missed by using a measure that is not sensitive to rapid improvement, though on the second trial the measures are more appropriately

rating scale by attempting

applied. A point frequently overlooked is that the success of a well-designed drug trial lies ultimately in the sensitivity of the instruments selected to evaluate change. Department of Psychiatry, Groote Schuur Hospital, Observatory, Cape,

Republic of South Africa. 6. 7. 8.

D. SMART P. J. V. BEUMONT G. C. W. GEORGE.

Jonsson, S., Karlmeter, G., Hallberg, T., Kronvall, G. Unpublished. Riff, L. J., Jackson, G. G. J. infect. Dis. 1971, 124, S98. Hamilton, M. Br. J. soc. clin. Psychol. 1967, 6, 278.

Letter: Serum-copper in sickle-cell anaemia.

285 require chronic pharmacotherapy as part of their treatment, intensifying the need for investigation of this possible side-effect. Department of P...
377KB Sizes 0 Downloads 0 Views