The alternative complement pathway comprises three component proteins C3, B, D and three regulatory proteins P, H and I. These plasma proteins represent the major humoral defense mechanism against infection in a non-immune host. The following topics are reviewed: biochemistry of the alternative pathway proteins; molecular mechanisms of activation and regulation of the pathway; involvement of the alternative pathway in human diseases.

Rheumatoid arthritis (RA) is an autoimmune disease whose diagnosis was long based solely upon the demonstration of rheumatoid factors (RF) which are IgM antibodies with anti-IgG specificity. The development of modern techniques which are more sensitive and/or detect non-IgM rheumatoid factors has reduced the percentage of presumptive seronegative RA. Immunological studies of the disease also reveal other evidences of polyclonal B-lymphocyte activation: hypergammaglobulinemia, high levels of beta-2-microglobulin and circulating immune complexes, presence of various autoantibodies (anti-collagen, antilymphocyte and, in some instances, anti-nuclear antibodies). These anomalies are found, not only in the blood, but above all in the synovial fluid, which explains the low synovial complement level. The disturbances of cellular immunity cannot yet be used for diagnostic purposes, but suggest that the physiopathologic mechanism of RA involves a decreased T-suppressor lymphocyte activity and/or B-cell unresponsiveness to suppressor influences.

With reference to two cases of Von Recklinghausen disease with malignant transformation the authors present the clinical features related to this transformation and the poor therapeutic results.

We report the case of an 85-year-old man with perfectly controlled hypertension and coronary insufficiency who presented with typical giant cell arteritis (GCA). Thirty-six hours after initiation of prednisolone therapy (1 mg/kg/d), acute coronary insufficiency with non-transmural infarction occurred. Outcome was favorable despite disturbances in heart rhythm. A review of the literature disclosed five cases of myocardial infarction related to GCA, confirmed upon pathological examination. Three out of five myocardial infarctions occurred between the third and seventh treatment days. These findings suggest that corticosteroids may be responsible for coronary complications which arise during the first days of GCA treatment. Furthermore, they justify close monitoring during the initial phase of treatment in patients with coronary diseases.

Clinical, biochemical and histological features of chronic hepatitis type B were studied in 29 children aged 8 months to 13 years. On entry into the study, all were known to have had hepatitis B surface antigen (HBsAg) with elevated serum transaminase levels for at least six months. A possible source of infection was found in 15 children. When they entered the study, all patients were anicteric and all but one asymptomatic. Hepatomegaly was detected in 15 patients and was associated with splenomegaly in two. Hypergammaglobulinemia was present in 4 children. Serological evaluation of hepatitis B virus markers showed evidence of complete viral replication (HBeAg positivity) in 24 cases and incomplete replication (anti-HBeAg positivity) in 5. Liver histology showed chronic persistent hepatitis (CPH) in 18 children, and chronic aggressive hepatitis (CAH) in 10 (3 moderately active and 7 with major signs of aggressivity) associated with cirrhosis in 5. One patient had only minimal histological changes. Evaluation of clinical, biochemical and virological parameters did not strictly parallel the histological diagnosis in terms of "activity" of the disease. Follow-up for a mean period of 13 months showed good clinical tolerance to the disease in both CPH and CAH patients. Only 2 children with CAH were given corticosteroids and/or azathioprine for a short period. During follow-up no children with active disease developed liver insufficiency or evidence of portal hypertension. No significant difference in the percentage of children who had seroconversion to antiHBe was found between CPH and CAH groups. Only one child with CAH became HBsAg negative.(ABSTRACT TRUNCATED AT 250 WORDS)

Twenty-one patients in a series of 283 treated surgically for primary hyperparathyroidism between 1960 and 1982, underwent reoperation. Eleven had been previously treated elsewhere. The initial cervicotomy was negative in fourteen cases, but had led to the ablation of one or more adenomas in seven. The reason for reoperation was recurrence or persistence of hyperparathyroidism (HPT). It was commenced by cervicotomy in the eleven patients initially treated elsewhere, and by cervicotomy and/or sternotomy for the others. Reoperation involved ablation of adenomas in thirteen cases, but was negative in the remaining eight. Three of the eight underwent a second reoperation, with success in two cases. Overall, reoperations led to ablation of sixteen adenomas in fifteen patients. Ten adenomas were ectopic, including eight located mediastinally . Ten sternotomies were performed, leading to ablation of four mediastinal adenomas. Postoperative complications included five recurrent paralyses and two severe cases of hypocalcemia. One patient with parathyroidal carcinoma died of malignant hypercalcemia. Fifteen of the twenty one patients (71%) were cured of their HPT. Basing themselves on these cases, and a review of the literature, the authors describe the indications and practical management of reoperative surgery for primary HPT.

A case of idiopathic splenomegaly with ceroid histiocytosis--the so-called sea-blue histiocytosis--is reported with reference to the literature. The histological, histochemical and ultrastructural features of stained sea-blue and ceroid-containing macrophages are described and their physiopathological significance is discussed. Attention is drawn to the distinctions, between idiopathic and secondary or associated forms, and the practical value of the pathological diagnosis is emphasized.

The aim of this study is to determine the best antibiotic in presumptive staphylococcal infection and/or bacteriologically established staphylococcal infection before results of antibiotic sensitivity tests are available. 382 strains were analyzed. Only sensitivity or resistance to antibiotics were considered. Vancomycin is the best antistaphylococcal agent (3% resistance rate on the 382 strains), (11% resistance rate on Methicillin-resistant Staphylococcus aureus strains). Pristinamycin and Virginiamycin also yield excellent scores but are less efficient against Methicillin-resistant staphylococci (21%). Cefalotin is still an excellent antistaphylococcal agent (7%). Fosfomycin is especially valuable against polyresistant staphylococci, with a 26% resistance rate on Methicillin-resistant Staphylococcus aureus. Lastly, significant increases in resistance rates relative to 1966 staphylococci strains are found only for penicillin (68% versus 78%) and rifamycin (3.6% versus 8%).

Osteoradionecrosis (ORN) is not exceptional, despite advances in irradiation techniques. Six cases are reported, involving the pelvis, coxofemoral joint, mandible and vertebrae; in this last case, the semiologic value of the lucent intrasomatic image seen on plain films and tomographies of the vertebrae is underscored. The irradiation dose (above 3 000 rad) is the chief factor in osteoradionecrosis, which may be precipitated by adjuvant factors and potentiating events such as trauma and infection. Pathologic study shows several lesions whose association is suggestive: cell lesions, osteoporosis, vascular lesions, and foci of necrosis. The pathogenic significance of lesions of bone cells is demonstrated, while the part played by vascular lesions is controversial. Involvement of the pelvis and hips following irradiation of pelvic carcinoma is the most common. The scapular girdle and ribs may be involved in irradiation for breast cancer. In involvement of the mandible, remarkable features are its frequency following irradiation of carcinoma of the mouth, the significant part played by potentiating factors, i.e. infection and trauma, severity of complications, i.e. fistulae and hemorrhage, and lastly difficulties of management. Among infrequent sites, involvement of the vertebrae is of interest as it may mimic collapse due to osteoporosis or metastasis. Diagnosis rests on an association of criteria, and fortunately bone biopsy is usually unnecessary. The clinical features, topographical characteristics and course of the disease allow differentiation from bone metastasis; it may be more difficult to distinguish postirradiation sarcoma, which is exceptional, or a number of benign conditions, such as aseptic necrosis, infectious osteoarthritis, and destructive coxarthrosis.

Four cases of monoclonal gammopathy associated with polyarteritis nodosa are reported. In view of the chronology of events and course of the disease, the connections between protein peak and polyarteritis nodosa can be considered. Management of polyarteritis nodosa is discussed according to the existence of a peak which may originate in myeloma. The part played by plasma exchanges is debated.

Three recent cases of retroperitoneal abscess provide an opportunity to review this complaint, which tends to be forgotten in this age of antibiotics. The most significant clinical sign is the discovery of an abdominal mass, and ultrasound is, today, a decisive diagnostic aid. Whatever the etiology - which is often difficult to establish - the essential part of the treatment consists in early and complete surgical drainage. This drainage may be associated with surgical treatment of the kidney, either simultaneously or subsequently, if this is required.

Serum parathyroid hormone was assayed in 16 elderly patients with primary, roentgenographically proved, articular chondrocalcinosis. Mean value, i.e. 4.10 + 1.16 mUI/ml, was compared to that of a control group of 16 subjects matched for sex and age without chondrocalcinosis, living in the same geriatric institution, i.e. 3.94 + 1.43 mUI/ml. The difference is not significant (t = 0,35). Latent hyperparathyroidism is therefore not demonstrated in primary proved articular chondrocalcinosis in the elderly.

Management of cancer in the elderly differs from that in other age groups only as far as concerns practical issues. The gradual deterioration of somatic and psychologic tolerance capacities is often associated with multiple pathological conditions which may delay diagnosis and hinder the implementation of therapy. Major therapeutic risks are mainly ascribable to chemotherapy which requires strict application of contraindications and close monitoring during treatment. Under these conditions, carefully determined by a thorough workup prior to treatment, the elderly patient, although fragile, can nevertheless benefit from adequate and efficient therapy. Although seemingly aggressive in some instances, this active outlook is preferable to systematic palliative therapy chosen only because of age, often constraining and not always useful or safe. Age in itself is not a reason for systematic abandon when significant results can be obtained without unacceptable risks until an advanced age through well-adjusted measures and continuous attention.