Analysis of the interferon system in African patients with acquired immunodeficiency syndrome

Serum interferon and in vitro production of alpha and gamma interferon by peripheral blood leucocytes were examined in 21 African patients with acquired immunodeficiency syndrome (AIDS) and in 15 African patients with AIDS-related complex. Interferon was detected in the serum of 44% of the patients with AIDS-related complex and in 70% of the patients with full-blown AIDS, and was characterized as an acid-labile alpha interferon. When compared to healthy blood donors, the interferon response of peripheral blood leucocytes to Newcastle Disease virus was impaired in 7 of 12 patients with AIDS-related complex and in 16 of 20 AIDS patients (p less than 0.005). Also, production of gamma interferon following stimulation with phytohaemagglutinin was diminished in 5 of 11 patients with AIDS-related complex and in 13 of 17 patients with AIDS (p less than 0.005). A high correlation was observed between the presence of circulating interferon and decreased in vitro production of gamma interferon, but not of alpha interferon. These results suggest that the impairment of in vitro production of gamma interferon can be used as a preclinical marker of AIDS.

Bovine leukemia virus-related antigens in lymphocyte cultures infected with AIDS-associated viruses

An earlier finding that lymphocytes from African patients with the acquired immune deficiency syndrome (AIDS) react with rabbit antiserum to purified antigens of bovine leukemia virus (BLV) prompted a study of the possible cross-reactions between a BLV-infected ovine cell line and human lymphocytes inoculated with a strain of lymphadenopathy syndrome-associated virus (LAV). A solid-phase radioimmunoassay was used to detect antigenic markers of the retroviruses. Crude extracts from short-term cultures of lymphocytes infected with LAV bound rabbit antisera to the LAV glycoprotein gp13 (molecular weight 13,000) and the BLV proteins p24 and gp51, but did not bind antibodies to the p24 of human T-cell leukemia virus type I (HTLV-I). Antiserum to LAV gp13 reacted with an ovine cell line producing BLV but also weakly with virus-free ovine cells. Lymphocyte cultures from four African patients with AIDS expressed BLV-related antigens within 6 to 10 days of culture, at the moment when particle-bound reverse transcriptase was produced. BLV-related antigens were induced in lymphocyte cultures from healthy individuals by addition of filtered supernatant or irradiated cells of the original culture. The antisera to BLV used in this study may prove useful for the detection of AIDS-associated viruses in short-term cultures of lymphocytes from AIDS patients or their contacts.

Thymopentin treatment in AIDS and pre-AIDS patients

Three pilot studies testing thymopentin in AIDS patients are presented. One study included 5 patients with the full-blown syndrome, all treated with 50 mg thymopentin 3 times a week by intravenous slow infusion; no immunologically nor clinically positive results were observed, indicating that the T cell pool in such patients is severely depleted. Six other patients with the prodromal stage of AIDS were treated 1 month with 50 mg thymopentin administered as an intravenous bolus injection 3 times weekly and thereafter for another month with same dose regimen as intravenous slow infusions. The patients on infusion therapy experienced statistically significant immunological improvements; these positive findings were paralleled with an improvement of the patients' clinical condition. These positive responses persisted for an average of 8 months. In another group of 5 pre-AIDS patients thymopentin was administered via the subcutaneous route using 15 mg 3 times weekly; only 1 patient revealed immunological and clinical improvement. In summary, only patients with the pre-AIDS syndrome are likely to benefit from immunomodulation therapy with thymopentin, and the mode of administration seems to be crucial.

Acquired immune deficiency syndrome in Belgium and its relation to Central Africa

During the years from 1979 until 1983, 40 cases of CDC-defined AIDS were seen in Belgium. Only two patients were Belgian male homosexuals. The other patients were Central Africans who lived in Belgium or who had travelled to Belgium for medical care. There was no evidence of an underlying immunosuppressive disease, and no history of homosexuality or intravenous drug abuse. The male:female ratio was 1.5. All patients had opportunistic infections. Five of them also had Kaposi's sarcoma. All patients tested had immunologic features of severe T-cell depression. The overall mortality was 42.5 percent. It is likely that AIDS is endemic now in Central Africa, and that the cases seen in Belgium represent only the tip of the iceberg.

Acquired immunodeficiency syndrome in Rwanda

To evaluate acquired immunodeficiency syndrome (AIDS) in central Africa a prospective study was done in Kigali, Rwanda, where Kaposi's sarcoma (KS) is endemic. During a 4 week period, 26 patients (17 males and 9 females) were diagnosed. 16 patients had opportunistic infections, associated with KS in only 2; 1 had multifocal KS alone; and 9 had clinical conditions consistent with prodromes of AIDS. All patients had severe T-cell defects characterised by cutaneous anergy, a striking decrease in the number of helper T cells, and a decreased OKT4:OKT8 ratio (mean 0.27). 21 of the 22 adult patients were living in urban centres and many of them were in the middle to upper income bracket. Most of the men were promiscuous heterosexuals and 43% of the females were prostitutes. No patient had a history of homosexuality, intravenous drug abuse, or transfusion in the previous 5 years. This study suggests that AIDS is present in central Africa as an entity probably unrelated to the well-known endemic African KS. An association of an urban environment, a relatively high income, and heterosexual promiscuity could be a risk factor for AIDS in Africa.

Treatment of severe staphylococcal infections with a rifampicin-minocycline association

During an outbreak, 25 severely impaired patients (mean age 62) presented with severe infections due to Staphylococcus aureus resistant to oxacillin and aminoglycosides. All strains were isolated in pure culture and diagnostic procedures included transtracheal puncture and bone biopsy. Median MICs were: oxacillin 50 mg/l, gentamicin 12.5 mg/l, tetracycline 25 gm/l, vancomycin 0.195 mg/l, rifampicin 0.097 mg/l and minocycline 0.195 mg/l. All patients were treated with rifampicin (600 mg/day) and minocycline (200 mg or 400 mg/day) administered together intravenously or orally bid. Mean duration of treatment was 22 days (range 5 to 119). Overall results were 19/25 infections cured and one improved. Five were failures due mostly to emergence of Staph. aureus resistant to rifampicin. No side effects were noted. These preliminary results suggest that rifampicin plus minocycline may be useful in the treatment of severe infections due to multi-resistant Staph. aureus.

Acquired immunodeficiency syndrome in African patients

Between May 1979 and April 1983, 18 previously healthy African patients were hospitalized in Belgium with opportunistic infections (cryptococcosis, Pneumocystis carinii pneumonia, central-nervous-system toxoplasmosis, progressive cutaneous herpes simplex virus infection, disseminated cytomegalovirus infection, candidiasis, or cryptosporidiosis) or Kaposi's sarcoma, or with both. Ten of them died. During the same period five other patients were hospitalized with an illness consistent with a prodrome of the acquired immunodeficiency syndrome (chronic lymphadenopathy, fever, weight loss, and diarrhea). All patients tested had a marked decrease in helper T cells; an inversion of the normal ratio of helper to suppressor T cells, and a decreased or absent blastogenic response of lymphocytes to mitogens. Twenty patients had anergy. There was no evidence of an underlying immunosuppressive disease and no history of blood-product transfusion, homosexuality, or intravenous-drug abuse. This syndrome in patients originating in Central Africa is similar to the acquired immunodeficiency syndrome reported in American patients.

Use of ceftazidime in the therapy of serious infections, including those due to multiresistant organisms

Ceftazidime was administered intravenously or intramuscularly or both in doses of 1 to 6 g per day to 33 patients with serious gram-negative bacillary infections (12 pulmonary, 10 urinary tract, 4 soft tissue, 4 intraabdominal, and 3 miscellaneous infections). Twenty-one patients were septicemic. We identified 20 isolates of members of the family Enterobacteriaceae and 13 isolates of Pseudomonas aeruginosa. Seventeen patients had failed to respond to previous antimicrobial therapy. A total of 23 patients were clinically cured, 7 patients improved, and 3 patients failed to respond to therapy. The selection or emergence of resistant organisms during treatment (mostly Candida spp., Staphylococcus aureus, and enterococci) was noted in 11 patients. Toxicity was minimal (reversible mild liver function abnormalities and eosinophilia). The results of this study suggest that ceftazidime is an effective and well-tolerated new cephalosporin for the therapy of serious infections due to susceptible gram-negative organisms.

Moxalactam therapy of serious infections

Twenty-four patients were treated with moxalactam for 25 serious infections. Nineteen patients were septicemic and 18 presented severe underlying diseases considered to impair the normal response to bacterial pathogens. All of the pathogens had MICs of less than 12 mg/l except one Pseudomonas aeruginosa strain with an MIC of 32 mg/l. The dosage ranged from 3 to 12 g/day; the route of administration was either i.v. or i.m. The duration of treatment was six to 26 days. Six patients had urinary tract infections (three bacteremia), four had pulmonary abscesses (two bacteremia), five had septic thrombophlebitis (five bacteremia) and ten had miscellaneous infections (nine bacteremia). Twenty-two (92%) patients responded favourably. Four patients (16.6%) developed superinfections due to organisms highly resistant to moxalactam: three Streptococcus faecalis, one Bacteroides fragilis and one Aspergillus flavus. Tolerance was good. Nine moderate adverse reactions were observed: three cases of transient eosinophilia, two of phlebitis, three hepatic enzyme alterations and one rash. Moxalactam kinetics were measured in serum from 15 patients with normal renal function after receiving 1 g i.v. over 30 min. The mean peak level after the infusion was 82.8 +/- 12.1 (SE) mg/l; the mean trough level 8 h later was 6.2 +/- 1.7 (SE) mg/l. The serum half-life was 2.6 +/- 0.6 (SE) h for the beta phase. Plasma clearance was 76.8 +/- 8.2 ml/min. Moxalactam was found to be highly effective in the therapy of life-threatening infections.

Ceftazidime as a single agent in the treatment of severe Pseudomonas aeruginosa infections

Ceftazidime was administered intravenously in doses of 1 to 6 g/day to 21 patients with serious Pseudomonas aeruginosa infections (12 pulmonary, 6 septicaemias, 3 urinary tract infections). Mean MIC was 1.0 mg/l. Eighteen (86%) of the 21 patients responded satisfactorily (cured or improved). The selection or emergence of resistant organisms during treatment (mostly Candida, Staphylococcus aureus, and enterococci) was noted in 6 patients. Toxicity was minimal (eosinophilia and reversible mild liver function abnormalities).

Serum sensitivity of strains isolated and antibodies against O antigen in gram-negative bacteraemia

The sensitivity of blood culture isolates to the bactericidal activity of normal human serum (NHS) has been studied in 101 patients with gram-negative sepsis. These results were compared with clinical status and outcome, and to the presence of specific IgG or IgM antibodies to O antigens of bacteraemic strains in autologous serum. 23% of the strains were markedly resistant, 27% markedly sensitive and 50% intermediately sensitive to the bactericidal activity of NHS. Shock or death occurred more frequently in immunocompromised patients and those infected with serum-resistant strains. IgG antibody titres to O antigens were significantly lower in patients with serum-resistant organisms regardless of their immune status. Resistance to natural bactericidal antibodies and low immunogenicity of the infecting organism, plus immunodeficiency in the host, may account for apparent increased virulence of some gram-negative bacilli.

Cefotaxime therapy of serious infections with multiresistant gram-negative bacilli

33 patients with serious gram-negative bacillary infections were treated with cefotaxime. In patients with normal renal function the dose varied between 1.5 to 4 g/day. 17 patients had urinary tract infections, 5 respiratory tract infections, 1 combined urinary tract infection and respiratory tract infection, and 10 miscellaneous infections. 16 patients had septicemia. 25 infections were due to pathogens resistant in vitro to ampicillin, cephalothin, gentamicin and/or tobramycin. 15 infections had failed to respond to ampicillin, cefazolin, gentamicin or tobramycin therapy. 32/33 patients responded favourably to cefotaxime (cure or improvement) but 4 patients developed superinfection with cefotaxime-resistant bacteria. No evidence of nephrotoxicity was observed except for a transient moderate rise in creatinine in one patient.

Immunological aspects to severe bacterial sepsis

In spite of discovery of new antibiotics and regular progress in intensive care, mortality from severe bacterial sepsis remains high. In this review the importance of cellular and humoral immunity in the pathogenesis and the outcome of severe infection is delineated. Immunological evaluation of patients in Intensive Care Units should be performed almost routinely in order to detect "high risk" patients with acquired defect in host-defence mechanisms. For these patients in addition to nutritional care, passive or active immunotherapy will help to restore resistance to bacterial infection.

Rapid diagnosis of bacterial meningitis

The diagnostic value of several investigations which may demonstrate bacteria or bacterial products in cerebrospinal fluid (CSF) samples from patients with meningitis are discussed. Estimation of CSF lactate and lactate dehydrogenase levels was found to be of value in the differential diagnosis of viral, bacterial and fungal meningitis and the detection of endotoxin by the Limulus amoebocyte lysate test was shown to be strongly suggestive of Gram-negative meningitis. The demonstration of bacterial capsular polysaccharides in CSF by counterimmuno-electrophoresis, latex agglutination and ELISA was of value in establishing a precise aetiological diagnosis, but the usefulness of these methods was limited by the lack of general availability of specific high-potency antisera which determine the sensitivity of the procedure. These screening tests do not replace standard analysis of CSF but provide useful ancillary evidence of meningitis. Negative results obtained from screening tests should not exclude a diagnosis of bacterial meningitis and a decision to withhold treatment should only be made after all available CSF results are evaluated in conjunction with the clinical features.

[Cefotaxime in the treatment of severe infections due to multiresistant Gram-negative bacilli (author's transl)]

Cefotaxime was used to treat 33 patients with serious Gram-negative bacillary infections. The dosage varied between 1.5 g and 4 g/day in patients without renal failure. Eighteen patients had urinary tract infections, 6 had pulmonary infections and 10 had miscellaneous infections. Sixteen patients were also bacteremic. Twenty-five infections were due to pathogens resistant to ampicillin, cephalothin, gentamicin and/or tobramycin, in vitro. Fifteen infections had failed to resolve during ampicillin, cefazolin, gentamicin or tobramycin therapy. Thirty-two patients responded favourably (cure or improvement). Four patients developed superinfection with cefotaxime-resistant bacteria. One patient developed mild reversible renal insufficiency. Cefotaxime is a very active cephalosporin with potential use in serious multi-resistant enterobacteria infections.

[Septicaemia and spontaneous peritonitis in the cirrhotic (author's transl)]

During a five year period 36 episodes of septicaemia in 32 patients with hepatic cirrhosis were documented. This represents 20% of the patients hospitalized with a decompensated cirrhosis and 1.1% of the patients with non decompensated cirrhosis. In patients with decompensated cirrhosis, enteric Gram-negative organisms were most frequently isolated (91% of the cases) and ascitis was infected in one third of the cases. No primary foci of infection were documented. On the contrary patients with a non decompensated cirrhosis had infection mostly with Gram-positive organisms (82%) and foci of infection (skin, throat) were documented in 38% of the cases. Infection by enteric organisms was associated with higher mortality than infection by non enteric organisms (68% vs 28%). Five patients with inappropriate antibiotic treatment died from septic shock. Spontaneous septicaemia and peritonitis are frequent complications if cirrhosis. There are potentially treatable causes of deterioration in the cirrhotic patient, necessitating prompt recognition and treatment.

[Defibrination syndrome during acute pancreatitis: 6 cases. Prospective studies of coagulation in 41 patients (author's transl)]

Studies of coagulation were performed prospectively in 41 patients with mild to moderately severe acute pancreatitis. Six patients (15%) presented with coagulation data suggestive of defibrination; two of them had clinical signs of bleeding. No other cause than pancreatitis was found in these 6 patients to account for coagulation abnormalities. Comparing the patients who presented defibrination to those who did not, no difference was observed in clinical course and admission values of serum amylase, fibrinogen, urea, calcium, glucose, transaminase levels, white blood cell count and arterial partial pressure of oxygen. Platelets counts and serum creatinine levels were respectively lower and higher in the first group of patients.

Clinical and pharmacological evaluation of different preparations of oral erythromycin

The activity of erythromycin stearate in respiratory tract infections was evaluated. This study involved 269 out-patients. Of these, 76 satisfied the strict criteria for detailed bacteriological study with positive cultures of a known pathogen before treatment and bacteriological follow-up after treatment. The results of erythromycin stearate were good against the haemolytic streptococcal infections. The activity of this antibiotic was shown to be insufficient against Haemophilus influenzae. A second clinical trial with 20 patients with acute exacerbations of chronic bronchitis demonstrated quite good activity from erythromycin ethylsuccinate and no intolerance when administered in a dose of 1 g q.i.d. The administration of 1 g of the ethylsuccinate immediately after a meal gave a peak serum concentration after 60 min of 3.36 micrograms/ml. Blood levels on the fourth day of this treatment showed some accumulation, concentrations of greater than 4 micrograms/ml being found at 30, 60 and 90 min after the dose. With its good absorption, its lack of toxicity and its reputation for good diffusion into bronchial secretions, we consider that erythromycin ethylsuccinate should have a major place in the treatment of respiratory tract infections.

Amoxicillin entry into human cerebrospinal fluid: comparison with ampicillin

The entry of amoxicillin and ampicillin into cerebrospinal fluid (CSF) of humans was studied in the absence of meningeal inflammation. Twelve volunteers received 33 mg of amoxicillin per kg intravenously over 30 min and nine volunteers received 33 mg of ampicillin per kg. The CSF specimens were sampled at 1, 2, and 4 h after the beginning of the infusion. Blood samples were obtained at the end of the infusion and at 45, 60, 90, 120, 180, and 240 min after the beginning of the infusion. Amoxicillin and ampicillin were both detected in the CSF. Ampicillin tended to give higher CSF levels than amoxicillin, although the difference was small. Serum concentrations of ampicillin equaled those of amoxicillin.

Is nasogastric suction necessary in acute pancreatitis?

Fifty-eight patients with mild to moderately severe acute pancreatitis were randomly allocated to treatment with or without nasogastric suction (27 and 31 patients respectively). Intravenous fluids and pethidine hydrochloride were also given. The two groups were comparable clinically at the start of the study. There were no differences between the two groups in the mean duration of the following features: abdominal pain or tenderness; absence of bowel movements; raised serum amylase concentration; time to resumption of oral feeding; and days in hospital. Prolonged hyperamylasaemia (serum amylase greater than 0.33 mU/l) occurred in one patient in the suction group and in three patients in the non-suction group. A mild recurrence of abdominal pain after resumption of oral feeding occurred in three patients in the suction group and in two patients in the non-suction group. Two patients in the suction group developed overt consumption coagulopathy and two others pulmonary complications. No patient in the non-suction group had complications. The findings suggest that most patients with mild to moderately severe acute pancreatitis do not benefit from nasogastric suction. The procedure should be elective rather than mandatory in treating this condition.

A low T3 syndrome in diabetic ketoacidosis

The pituitary-thyroid axis was investigated in nineteen euthyroid patients with severe diabetic ketoacidosis. A 'low T3 syndrome' was found, with the following characteristics: lowered serum concentrations of triiodothyronine (T3), increased reverse triiodothyronine (rT3), slightly low thyroxine (T4), normal thyrotrophin (TSH), slightly increased triiodothyronine uptake (RT3U) values, and a blunted TSH response to thyrotrophin-releasing hormone (TRH). These disturbances in thyroid-function tests required several days good control of the diabetes to be corrected, at least partially. The data suggest the presence of an abnormal extrathyroidal T4 metabolism as well as a pituitary defect. Caution is recommended in the interpretation of thyroid-function tests during and several days after the treatment of diabetic ketoacidosis.

Limulus test and meningitis

Images

Treatment of diabetic coma with small intravenous insulin boluses

The clinical efficacy of small intravenous boluses of insulin in treating diabetic decompensation was tested in 23 patients presenting in either a ketoacidotic or a nonketotic diabetic coma. In addition to the usual ionic and fluid replacement, the patients received hourly intravenous injections of insulin 5 IU. This dose lowered blood glucose levels in all but two patients. In the patients who responded the percentage decrease in glycaemia was similar whatever the initial glucose concentration and averaged (+/-SE of mean) 50+/-3% in five hours. Close monitoring of insulin and glucose concentrations after intravenous insulin in three patients showed that despite the short half life of insulin the effect of the intravenous bolus lasted for about 60 minutes. The overall clinical effectiveness of this type of treatment is comparable to that of the other low-dose regimens. Owing to its simplicity, this technique of insulin administration seems most suitable for the routine treatment of diabetic coma.

[Contribution of the "limulus test" to the diagnosis of endotoxemias and meningitis due to gram negative bacteria]

The "limulus test" may be used to detect the endotoxins of Gram negative organisms. Applied to the cerebrospinal fluid (79 specimens from 64 patients) it proved itself to be a very important contribution to the differential diagnosis of purulent meningitis (95% positive results, no false positives). However it can be used on the plasma only in patients with shock of suspected endotoxic origin.