Bacterial vaginosis is associated with prematurity and vaginal fluid mucinase and sialidase: results of a controlled trial of topical clindamycin cream

OBJECTIVE

The pathogenesis of preterm birth and other adverse pregnancy outcomes linked with reproductive tract infection remains poorly understood. Mucolytic enzymes, including mucinases and sialidases (neuraminidase), are recognized virulence factors among enteropathogens and bacteria that cause periodontal infection. Perturbation of maternal cervicovaginal mucosa membrane host defenses by such enzyme-producing microorganisms may increase the risk of subclinical intrauterine infection during pregnancy and thus increase risks of preterm birth.

STUDY DESIGN

We prospectively evaluated vaginal fluid mucinase and sialidase and selected cervicovaginal bacteria along with pregnancy outcomes in 271 women. Within this study, women with bacterial vaginosis (16 to 27 week' gestation) were treated with 2% clinadmycin vaginal cream or placebo. Enzyme, microbial findings, treatment effects, and pregnancy outcomes were compared among drug- and placebo-treated women and control women without bacterial vaginosis.

RESULTS

Presence of bacterial vaginosis at intake was associated with increased risk of preterm birth (relative risk 3.3, 95% confidence interval 1.2 to 9.1, p = 0.02), premature rupture of membranes (relative risk 3.8, 95% confidence interval 1.6 to 9.0, p = 0.002), and preterm premature rupture of membranes. Mucinase and sialidase activities were more commonly identified, and they occurred in higher concentrations, if present, in women with bacterial vaginosis (mucinase: 44.3% with bacterial vaginosis vs 27.4% without, p = 0.007; sialidase: 45% with bacterial vaginosis vs 12% without p < 0.001). Sialidase activity was associated with bacterial vaginosis-linked organisms (Gardnerella vaginalis, Mobiluncus spp, and Mycoplasma hominis) and Chlamydia trachomatis and yeast species; mucinase activity was associated only with bacterial vaginosis-linked microorganisms. Clindamycin, 2% cream, was effective treatment for bacterial vaginosis and temporarily reduced mucinase and sialidase activities. Topical treatment of bacterial vaginosis did not reduce risks of perinatal morbidity. Women with persistent or recurrent sialidase 8 weeks after treatment were at increased risk of preterm birth (15.6% vs 7.4%) premature rupture of membranes (30% vs 15%), and low birth weight (20% vs 3%, relative risk 6.8, 95% confidence interval 1.6 to 28.1).

CONCLUSIONS

Persistence of sialidase-producing vaginal microorganisms in numbers sufficient to increase vaginal fluid sialidase activity may be a risk factor for possibly preventable subclinical intrauterine infection and preterm birth. This study confirms and further informs our understanding of the association of bacterial vaginosis and preterm birth; studies to evaluate whether systemic treatment for bacterial vaginosis can effectively reduce vaginal mucolytic enzymes and risks of prematurity and other morbid outcomes are continuing.

Biochemical and functional properties of recombinant human sickle hemoglobin expressed in yeast

Previous studies had indicated that recombinant and natural human sickle hemoglobin had similar chemical properties (Martin de Llano, J. J., Schneewind, O., Stetler, G., and Manning, J. M. (1993) Proc. Natl. Acad. Sci. U.S.A. 90, 918-922). In the present study, additional biochemical and physiological characterization of some primary through quaternary structural features of recombinant sickle hemoglobin are described. The molecular weight of the purified recombinant sickle hemoglobin was identical to natural sickle hemoglobin as determined by mass spectrometry, thus excluding extensive post-translational modification in the yeast system. Carboxypeptidases A and B together catalyzed the release of COOH-terminal amino acids at the same rate for recombinant and natural hemoglobin S, consistent with identity in their primary and secondary structures in this region of the molecule. The tryptic peptide maps of natural and recombinant hemoglobins were practically indistinguishable, indicating the same internal protein sequences for recombinant and natural hemoglobins. As a probe of the secondary structure of recombinant sickle Hb, the reactivity of the SH group of Cys-93(beta) was investigated for the glutathione sickle hemoglobin adduct, which has significant anti-gelling and anti-sickling properties. The position of glutathione at Cys-93(beta) was established by direct mass spectrometric analysis of enzyme digests; reduction of this derivative to the unmodified chains was also observed by mass spectrometry and by isoelectric focusing. The oxygen equilibrium curves of recombinant and natural sickle hemoglobin at high protein concentration were superimposable with identical Hill coefficients of 3.3. The response of recombinant sickle hemoglobin to chloride with respect to a lowered oxygen affinity was identical to that of natural sickle hemoglobin. The gelation properties of recombinant and natural sickle hemoglobins were identical at the high hemoglobin concentrations that occur in the red cell. Therefore, the yeast expression system synthesizes a completely functional recombinant sickle hemoglobin with the same biochemical and physiological properties as natural sickle hemoglobin with respect to features characteristic of its primary through quaternary structures.

Acute lymphoid leukemia associated with Maffucci's syndrome

PURPOSE

Maffucci's syndrome is a nonhereditary congenital disorder associated with multiple enchondromas, soft tissue hemangiomas, or lymphangiomas. It carries an associated high risk of the development of malignant neoplasms, particularly sarcomatous transformation of an enchondroma, as well as other malignant mesodermal and nonmesodermal neoplasms. Hematopoietic malignancies arising in Maffucci's syndrome are exceedingly rare. We report the case of a 14-year-old girl with Maffucci's syndrome who developed acute lymphoid leukemia.

PATIENTS AND METHODS

The patient presented at 18 months of age with enchondromatosis. Maffucci's syndrome was established at 10 years of age after the appearance of multiple hemangiomas.

RESULTS

At 14 years of age the patient developed fatigue, frequent nosebleeds, easy bruising, and weight loss, with circulating blasts in the peripheral blood. Bone marrow examination showed replacement of marrow spaces with leukemic blasts. Immunohistochemical and flow cytometric findings were consistent with a diagnosis of acute lymphoblastic leukemia with myeloid antigen expression.

CONCLUSIONS

The occurrence of acute leukemia in a patient with Maffucci's syndrome may represent predisposition to yet another malignancy and reflect further expression of a generalized mesodermal dysplasia in these patients. It also emphasizes the need for aggressive surveillance in patients with Maffucci's syndrome.

Evidence supporting the superiority of intraperitoneal cisplatin compared to intraperitoneal carboplatin for salvage therapy of small-volume residual ovarian cancer

PURPOSE

To examine the relative efficacy of cisplatin-based intraperitoneal (IP) therapy versus carboplatin-based IP therapy as salvage treatment of small-volume residual ovarian cancer.

PATIENTS AND METHODS

We retrospectively examined the surgically defined response rates of patients with ovarian cancer treated at the Memorial Sloan-Kettering Cancer Center on four organoplatinum-based salvage IP trials (cisplatin/etoposide, cisplatin/cytarabine, carboplatin/etoposide, carboplatin/etoposide + recombinant human erythropoietin). Additional criteria for inclusion in this analysis were: (a) small-volume residual disease (microscopic disease only or largest residual tumor mass < or = 0.5 cm) when IP therapy was initiated; (b) prior response to organoplatinum-based systemic therapy; (c) laparotomy evaluation for response to the IP salvage program.

RESULTS

The surgically documented complete response rate for patients with microscopic disease treated with cisplatin-based or carboplatin-based therapy was 46% (6/13) versus 38% (6/16), respectively (P > 0.25). In contrast, the surgically documented overall and complete response rates for patients with small-volume macroscopic disease treated with cisplatin or carboplatin were 71% (12/17) versus 32% (6/19) (P < 0.05, chi 2 test with Yates' correction), and 41% (6/17) versus 11% (2/19) (p < 0.1), respectively.

CONCLUSION

In agreement with experimental data demonstrating that the concentration of platinum within tumor is higher following equimolar doses of cisplatin, compared to carboplatin, we have observed, in this retrospective analysis, a higher surgically documented response rate for patients with small-volume residual macroscopic ovarian cancer receiving salvage cisplatin-based IP therapy. While a randomized trial will be required to definitively address the question of the relative effectiveness of the two commercially available organoplatinum agents for IP treatment of ovarian cancer, our data suggest that cisplatin is the superior agent for regional therapy in this disease.

Mitomycin-C plus a 3-day continuous intravenous infusion of 5-fluorouracil: an inactive salvage regimen for platinum-resistant ovarian carcinoma

In a Phase II trial, patients with refractory ovarian cancer were given 10 mg/m2 mitomycin-C i.v. every 8 weeks and 1000 mg/m2/day 5-fluorouracil for 3 consecutive days by continuous intravenous infusion repeated every 4 weeks. Sixteen heavily pretreated patients with platinum-resistant disease were treated and no major responses were observed. Only 2 patients required subsequent dose reduction for myelotoxicity. No sign of gastrointestinal toxicity was seen. This regimen is inactive as salvage treatment for refractory ovarian cancer.

Diethyldithiocarbamate chemoprotection of carboplatin--induced hematological toxicity

Carboplatin therapy has a more favorable toxicity profile than cisplatin and, given in appropriate doses, is equivalent in efficacy to cisplatin for suboptimal ovarian cancer. However myelosuppression frequently curtails therapy with carboplatin. Diethyldithiocarbamate (DDTC) is a thiol compound and heavy-metal-chelating agent that has been shown to protect against carboplatin-induced bone marrow suppression in animal models. This pilot study was undertaken to evaluate the ability of DDTC to ameliorate the degree and/or duration of myelosuppression from carboplatin chemotherapy in patients with relapsed ovarian cancer. Ten patients who had previously demonstrated a response to platinum-based chemotherapy, were treated with single-agent intravenous carboplatin 400 mg/m2 administered over 30-60 min every 4 weeks. Patients received their first cycle of carboplatin without DDTC, and their second cycle with DDTC. DDTC at 600 mg/m2 was infused over 3 h commencing 30 min prior to carboplatin and was well tolerated. Treatment with DDTC did not decrease the degree of leukopenia or thrombocytopenia associated with carboplatin chemotherapy, nor did it decrease the duration of myelosuppression. This clinical study demonstrates no evidence of a bone-marrow-protective effect for this dose and schedule of DDTC in patients receiving carboplatin chemotherapy.

The use of recombinant human erythropoietin to prevent carboplatin-induced anemia

Anemia is a frequent and potentially serious toxicity associated with the use of carboplatin, particularly when this agent is administered in the salvage setting. In an effort to evaluate a possible role for human erythropoietin (rh-E) in preventing or minimizing carboplatin-induced anemia we analyzed the impact of the agent on anemia and transfusion requirements of women with ovarian cancer who were treated on one of two nonrandomized trials employing identical second-line carboplatin-based intraperitoneal regimens, with the only difference in the regimens being the addition of rh-E (Study 1, without rh-E; Study 2, with rh-E). There was a statistically significant difference in the incidence of documented nadir hemoglobin levels of < 9 g/dl (Study 1, 60%; Study 2, 13%; P < 0.005) and < 8 g/dl (Study 1, 33%; Study 3, 6%; P < 0.05). We also observed a threefold reduction in transfusion requirements with the use of rh-E (Study 1, 23%; Study 2, 6%), but this difference was not statistically significant with the limited sample size evaluated. In this nonrandomized comparison of two identical chemotherapy programs we have demonstrated that rh-E significantly reduced the incidence and severity of anemia associated with carboplatin-based chemotherapy. A randomized trial examining the potential impact of rh-E on carboplatin-induced anemia and transfusion requirements is warranted.

Salvage intraperitoneal mitoxantrone therapy of ovarian cancer: influence of increasing the volume of treatment

Despite the demonstrated activity of intraperitoneal mitoxantrone in patients with small volume-platinum-refractory ovarian cancer, previous reports have revealed that many patients fail to achieve adequate distribution of the cytotoxic drug throughout the peritoneal cavity when delivered in a "standard" 2-liter treatment volume. In an effort to improve the distribution and therapeutic efficacy of intraperitoneal mitoxantrone, 22 patients with platinum-refractory ovarian cancer were treated with the drug at a dose of 10 mg/m2 given in 2 liters of normal saline followed by an additional 1-2 liters every 2 weeks for eight cycles. The surgically defined complete response rate in 17 patients evaluable for response with platinum-refractory ovarian cancer was 24%, with an overall response rate of 29%. Of 18 in which the influence of treatment volume could be examined (4 patients developed catheter failure), 12 (67%) were able to tolerate a 4-liter treatment volume for > 80% of courses, with a total of 15 patients (83%) receiving treatment with a minimum of a 3-liter treatment volume. We conclude that it is possible to safely increase the intraperitoneal treatment volume to 3-4 liters in most patients undergoing this therapeutic strategy. While the impact on therapeutic efficacy of expanding the volume employed for cytotoxic drug delivery remains to be defined, in theory this approach may optimize the opportunity for agents achieving high-intraperitoneal concentrations to produce their maximal cytotoxic effect.